View Filing Data

Document And Entity Information - shares	3 Months Ended
Mar. 31, 2012	Apr. 23, 2012
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Entity Registrant Name	UNITIL CORP
Entity Central Index Key	0000755001
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		10,990,496

Consolidated Statements Of Earnings - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Operating Revenues
Gas	$ 64.2	$ 65.9
Electric	48.7	48.2
Other	1.3	1.3
Total Operating Revenues	114.2	115.4
Operating Expenses
Purchased Gas	36.5	40.5
Purchased Electricity	31.1	31.2
Operation and Maintenance	13.4	12.2
Conservation & Load Management	1.9	1.5
Depreciation and Amortization	8.3	7.9
Provisions for Taxes:
Local Property and Other	3.7	3.3
Federal and State Income	5.3	5.4
Total Operating Expenses	100.2	102.0
Operating Income	14.0	13.4
Other Non-Operating Expense	0.1	0.1
Income Before Interest Expense	13.9	13.3
Interest Expense, Net	4.9	4.6
Net Income	9.0	8.7
Less: Dividends on Preferred Stock
Earnings Applicable to Common Shareholders	$ 9.0	$ 8.7
Weighted Average Common Shares Outstanding - Basic (000's)	10,917	10,860
Weighted Average Common Shares Outstanding - Diluted (000's)	10,921	10,861
Earnings Per Common Share (Basic and Diluted)	$ 0.83	$ 0.81
Dividends Declared Per Share of Common Stock	$ 0.69	$ 0.69

Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Utility Plant:
Electric	$ 339.6	$ 333.3	$ 325.1
Gas	390.0	382.3	362.3
Common	29.9	29.8	30.7
Construction Work in Progress	21.0	28.3	13.9
Total Utility Plant	780.5	773.7	732.0
Less: Accumulated Depreciation	268.3	263.0	256.0
Net Utility Plant	512.2	510.7	476.0
Current Assets:
Cash	8.2	7.5	6.6
Accounts Receivable, Net	47.9	44.2	45.7
Accrued Revenue	37.4	56.6	33.9
Gas Inventory	6.8	14.8	0.7
Materials and Supplies	3.9	3.6	3.4
Prepayments and Other	5.0	4.5	4.4
Total Current Assets	109.2	131.2	94.7
Noncurrent Assets:
Regulatory Assets	141.4	139.8	139.6
Other Noncurrent Assets	20.4	18.5	26.4
Total Noncurrent Assets	161.8	158.3	166.0
TOTAL	783.2	800.2	736.7
Capitalization:
Common Stock Equity	193.6	191.7	190.5
Preferred Stock	2.0	2.0	2.0
Long-Term Debt, Less Current Portion	287.7	287.8	288.2
Total Capitalization	483.3	481.5	480.7
Current Liabilities:
Long-Term Debt, Current Portion	0.5	0.5	0.5
Accounts Payable	18.7	26.4	22.5
Short-Term Debt	77.6	87.9	50.6
Energy Supply Contract Obligations	12.6	21.1	9.1
Taxes Payable	0.4	1.0	0.1
Other Current Liabilities	22.4	17.5	21.1
Total Current Liabilities	132.2	154.4	103.9
Deferred Income Taxes	52.1	46.3	48.7
Noncurrent Liabilities:
Energy Supply Contract Obligations	4.0	4.2	10.4
Retirement Benefit Obligations	89.5	91.2	70.3
Environmental Obligations	14.5	14.5	14.5
Other Noncurrent Liabilities	7.6	8.1	8.2
Total Noncurrent Liabilities	115.6	118.0	103.4
TOTAL	$ 783.2	$ 800.2	$ 736.7

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Operating Activities:
Net Income	$ 9.0	$ 8.7
Adjustments to Reconcile Net Income to Cash Provided by Operating Activities:
Depreciation and Amortization	8.3	7.9
Deferred Tax Provision	5.3	4.5
Changes in Working Capital Items:
Accounts Receivable	(3.7)	(8.8)
Accrued Revenue	19.2	12.8
Taxes Refundable / Payable	(0.6)	7.6
Gas Inventory	8.0	9.9
Accounts Payable	(7.7)	(4.0)
Other Changes in Working Capital Items	(1.7)	(0.2)
Deferred Regulatory and Other Charges	(4.2)	(2.5)
Other, net	(1.5)	0.5
Cash Provided by Operating Activities	30.4	36.4
Investing Activities:
Property, Plant and Equipment Additions	(9.1)	(10.8)
Cash (Used in) Investing Activities	(9.1)	(10.8)
Financing Activities:
Repayment of Short-Term Debt	(10.3)	(16.2)
Repayment of Long-Term Debt	(0.1)	(0.1)
Net Decrease in Gas Inventory Financing	(6.5)	(7.8)
Dividends Paid	(3.8)	(3.8)
Proceeds from Issuance of Common Stock	0.3	0.3
Other, net	(0.2)	(0.3)
Cash (Used in) Financing Activities	(20.6)	(27.9)
Net Increase (Decrease) in Cash	0.7	(2.3)
Cash at Beginning of Period	7.5	8.9
Cash at End of Period	8.2	6.6
Supplemental Cash Flow Information:
Interest Paid	3.1	3.1
Income Taxes Paid (Refunded)	$ 0.6	$ (6.9)

Summary Of Significant Accounting Policies

3 Months Ended

Mar. 31, 2012

Summary Of Significant Accounting Policies [Abstract]

Summary Of Significant Accounting Policies

NOTE 1 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Nature of Operations – Unitil Corporation (Unitil or the Company) is a public utility holding company. Unitil and its subsidiaries are subject to regulation as a holding company system by the Federal Energy Regulatory Commission (FERC) under the Energy Policy Act of 2005. The following companies are wholly-owned subsidiaries of Unitil: Unitil Energy Systems, Inc. (Unitil Energy), Fitchburg Gas and Electric Light Company (Fitchburg), Northern Utilities, Inc. (Northern Utilities), Granite State Gas Transmission, Inc. (Granite State), Unitil Power Corp. (Unitil Power), Unitil Realty Corp. (Unitil Realty), Unitil Service Corp. (Unitil Service) and its non-regulated business unit Unitil Resources, Inc. (Unitil Resources). Usource, Inc. and Usource L.L.C. are subsidiaries of Unitil Resources.

The Company's results are expected to reflect the seasonal nature of the natural gas businesses. Accordingly, the Company expects that results of operations will be positively affected during the first and fourth quarters, when sales of natural gas are typically higher, and negatively affected during the second and third quarters, when gas operating and maintenance expenses usually exceed sales margins in the period.

Unitil's principal business is the local distribution of electricity in the southeastern seacoast and state capital regions of New Hampshire and the greater Fitchburg area of north central Massachusetts, and the local distribution of natural gas in southeastern New Hampshire, portions of southern and central Maine and in the greater Fitchburg area of north central Massachusetts. Unitil has three distribution utility subsidiaries, Unitil Energy, which operates in New Hampshire, Fitchburg, which operates in Massachusetts, and Northern Utilities, which operates in New Hampshire and Maine (collectively referred to as the distribution utilities).

Granite State is a natural gas transportation pipeline, operating 86 miles of underground gas transmission pipeline primarily located in Maine and New Hampshire. Granite State provides Northern Utilities with interconnection to three major natural gas pipelines and access to domestic natural gas supplies in the south and Canadian natural gas supplies in the north. Granite State derives its revenues principally from the transportation services provided to Northern Utilities and, to a lesser extent, third –party marketers.

A fifth utility subsidiary, Unitil Power, formerly functioned as the full requirements wholesale power supply provider for Unitil Energy. In connection with the implementation of electric industry restructuring in New Hampshire, Unitil Power ceased being the wholesale supplier of Unitil Energy on May 1, 2003 and divested of its long-term power supply contracts through the sale of the entitlements to the electricity associated with various electric power supply contracts it had acquired to serve Unitil Energy's customers.

Unitil also has three other wholly-owned subsidiaries: Unitil Service; Unitil Realty; and Unitil Resources. Unitil Service provides, at cost, a variety of administrative and professional services, including regulatory, financial, accounting, human resources, engineering, operations, technology, energy management and management services on a centralized basis to its affiliated Unitil companies. Unitil Realty owns and manages the Company's corporate office in Hampton, New Hampshire and leases this facility to Unitil Service under a long-term lease arrangement. Unitil Resources is the Company's wholly-owned non-regulated subsidiary. Usource, Inc. and Usource L.L.C. (collectively, Usource) are wholly-owned subsidiaries of Unitil Resources. Usource provides brokering and advisory services to large commercial and industrial customers in the northeastern United States.

Basis of Presentation – The accompanying unaudited consolidated financial statements of Unitil have been prepared in accordance with the instructions to Form 10-Q and include all of the information and footnotes required by generally accepted accounting principles. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. The results of operations for the three months ended March 31, 2012 are not necessarily indicative of results to be expected for the year ending December 31, 2012. For further information, please refer to Note 1 of Part II to the Consolidated Financial Statements – "Summary of Significant Accounting Policies" of the Company's Form 10-K for the year ended December 31, 2011, as filed with the Securities and Exchange Commission (SEC) on February 1, 2012, for a description of the Company's Basis of Presentation.

Derivatives – The Company has a regulatory approved hedging program for Northern Utilities designed to fix a portion of its gas supply costs for the coming year of service. In order to fix these costs, the Company purchases natural gas futures contracts on the New York Mercantile Exchange (NYMEX) that correspond to the associated delivery month. Any gains or losses resulting from the change in the fair value of these derivatives are passed through to ratepayers directly through a regulatory commission approved recovery mechanism. The fair value of these derivatives is determined using Level 2 inputs (valuations based on quoted prices available in active markets for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, inputs other than quoted prices that are directly observable, and inputs derived principally from market data), specifically based on the NYMEX closing prices for outstanding contracts as of the balance sheet date. As a result of the ratemaking process, the Company records gains and losses resulting from the change in fair value of the derivatives as regulatory liabilities or assets, then reclassifies these gains or losses into Purchased Gas when the gains and losses are passed through to customers in accordance with rate reconciling mechanisms.

As of March 31, 2012, March 31, 2011 and December 31, 2011, the Company had 1.5 billion, 1.3 billion and 1.6 billion cubic feet (BCF), respectively, outstanding in natural gas purchase contracts under its hedging program.

The tables below show derivatives, which are part of the regulatory approved hedging program, that are not designated as hedging instruments under FASB ASC 815-20. As discussed above, the change in fair value related to these derivatives is recorded initially as a Regulatory Asset then reclassified to Purchased Gas in accordance with the recovery mechanism. The tables below include disclosure of the Regulatory Asset and reclassifications from the Regulatory Asset into Purchased Gas.


Fair Value Amount (millions) Offset in Regulatory Assets⁽¹⁾, as of:
		Fair Value
Description	Balance Sheet Location	March 31, 2012		March 31, 2011		December 31, 2011
Natural Gas Futures Contracts	Other Current Liabilities	$	1.8	$	0.4	$	1.7

Natural Gas Futures Contracts	Other Noncurrent Liabilities		0.2		—		0.6

Total		$	2.0	$	0.4	$	2.3

⁽¹⁾	The current portion of Regulatory Assets are recorded as Accrued Revenue on the Company's unaudited Consolidated Balance Sheets.


	Three Months Ended March 31,
(millions)	2012		2011
Amount of Loss Recognized in Regulatory Assets for Derivatives:
Natural Gas Futures Contracts	$	1.3	$	0.1
Amount of Loss Reclassified into unaudited Consolidated Statements of Earnings⁽ ² ⁾:
Purchased Gas	$	1.6	$	0.7

⁽ ² ⁾

These amounts are offset in the unaudited Consolidated Statements of Earnings with Accrued Revenue and therefore there is no effect on earnings.

Allowance for Doubtful Accounts – The Company recognizes a provision for doubtful accounts each month based upon the Company's experience in collecting electric and gas utility service accounts receivable in prior years. At the end of each month, an analysis of the delinquent receivables is performed which takes into account an assumption about the cash recovery of delinquent receivables. The analysis also calculates the amount of written-off receivables that are recoverable through regulatory rate reconciling mechanisms. The Company's distribution utilities are authorized by regulators to recover the costs of their energy commodity portion of bad debts through rate mechanisms. Evaluating the adequacy of the Allowance for Doubtful Accounts requires judgment about the assumptions used in the analysis, including expected fuel assistance payments from governmental authorities and the level of customers enrolling in payment plans with the Company.

The Allowance for Doubtful Accounts as of March 31, 2012, March 31, 2011 and December 31, 2011, which are included in Accounts Receivable, Net on the accompanying unaudited consolidated balance sheets, were as follows:

(Millions)

March 31,

December 31,

2012

2011

Allowance for Doubtful Accounts

2.6

3.0

2.3

Subsequent Events – The Company has evaluated all events or transactions through the date of this filing. During this period, the Company did not have any material subsequent events that impacted its unaudited consolidated financial statements.

Reclassifications – Based on the Company's analysis certain amounts previously reported have been reclassified to improve the financial statements' presentation and to conform to current year presentation.

Recently Issued Pronouncements – There are no recently issued pronouncements applicable to the Company that have not already been adopted.

Common Stock And Preferred Stock

3 Months Ended

Mar. 31, 2012

Common Stock And Preferred Stock [Abstract]

Common Stock And Preferred Stock

NOTE 3 – COMMON STOCK AND PREFERRED STOCK

Common Stock

The Company's common stock trades under the symbol, "UTL."

On April 21, 2011, the Company's shareholders approved an increase in the authorized shares of the Company's common stock. Shareholders approved an amendment to the Company's Articles of Incorporation to increase the authorized number of shares of the Company's common stock, from 16,000,000 shares to 25,000,000 shares in the aggregate. The Company had 10,989,389, 10,925,136 and 10,954,065 of common shares outstanding at March 31, 2012, March 31, 2011 and December 31, 2011, respectively.

Dividend Reinvestment and Stock Purchase Plan – During the first quarter of 2012, the Company sold 9,724 shares of its common stock, at an average price of $27.19 per share, in connection with its Dividend Reinvestment and Stock Purchase Plan (DRP) and its 401(k) plans resulting in net proceeds of approximately $264,000. The DRP provides participants in the plan a method for investing cash dividends on the Company's common stock and cash payments in additional shares of the Company's common stock.

Stock Plan – The Company maintains the Unitil Corporation Amended and Restated 2003 Stock Plan (the Stock Plan). Participants in the Stock Plan are selected by the Compensation Committee of the Board of Directors from the Company's, its subsidiaries' and its affiliates' employees, directors and consultants to receive an award of shares of Company common stock (including restricted shares) or of restricted stock units. The Compensation Committee has the power to determine the sizes of awards; determine the terms and conditions of awards in a manner consistent with the Stock Plan; construe and interpret the Stock Plan and any agreement or instrument entered into under the Stock Plan as they apply to participants; establish, amend, or waive rules and regulations for the Stock Plan's administration as they apply to participants; and, subject to the provisions of the Stock Plan, amend the terms and conditions of any outstanding award to the extent such terms and conditions are within the discretion of the Compensation Committee as provided for in the Stock Plan. On April 19, 2012, the Company's shareholders approved an amendment to the Stock Plan to, among other things, increase the maximum number of shares of common stock available for awards to plan participants.

Outstanding awards of restricted shares fully vest over a period of four years at a rate of 25% each year. During the vesting period, dividends on restricted shares underlying the award may be credited to a participant's account. Awards may be grossed up to offset the participant's tax obligations in connection with the award. Prior to the end of the vesting period, the restricted shares are subject to forfeiture if the participant ceases to be employed by the Company other than due to the participant's death. The maximum number of shares of restricted stock available for awards to participants under the Stock Plan was 177,500 as of March 31, 2012, and was increased on April 19, 2012 to 677,500. The maximum aggregate number of shares or restricted stock units that may be awarded in any one calendar year to any one participant is 20,000. In the event of any change in capitalization of the Company, the Compensation Committee is authorized to make an equitable adjustment to the number and kind of shares of common stock that may be delivered under the Stock Plan and, in addition, may authorize and make an equitable adjustment to the Stock Plan's annual individual award limit.

On February 3, 2012, 25,600 restricted shares were issued in conjunction with the Stock Plan with an aggregate market value at the date of issuance of $720,896. There were 53,780 and 49,089 non-vested shares under the Stock Plan as of March 31, 2012 and 2011, respectively. The weighted average grant date fair value of these shares was $24.78 and $22.17, respectively. The compensation expense associated with the issuance of shares under the Stock Plan is being recognized over the vesting period and was $0.3 million and $0.1 million for the three months ended March 31, 2012 and 2011, respectively. At March 31, 2012, there was approximately $1.5 million of total unrecognized compensation cost under the Stock Plan which is expected to be recognized over approximately 2.9 years. There were no forfeitures or cancellations under the Stock Plan during the three months ended March 31, 2012.

There were no restricted stock units issued under the Stock Plan during the three months ended March 31, 2012.

Preferred Stock

Details on preferred stock at March 31, 2012, March 31, 2011 and December 31, 2011 are shown below:

(Amounts in Millions)


	March 31,				December 31,
	2012		2011		2011
Preferred Stock
Unitil Energy Preferred Stock, Non-Redeemable, Non-Cumulative:
6.00% Series, $100 Par Value,	$	0.2	$	0.2	$	0.2
Fitchburg Preferred Stock, Redeemable, Cumulative:
5.125% Series, $100 Par Value		0.8		0.8		0.8
8.00% Series, $100 Par Value		1.0		1.0		1.0

Total Preferred Stock	$	2.0	$	2.0	$	2.0

There were 2,250, 2,250 and 2,250 shares of Unitil Energy's 6.00% Series Preferred Stock outstanding at March 31, 2012, March 31, 2011 and December 31, 2011, respectively. There were 7,861, 7,901 and 7,861 shares of Fitchburg's 5.125% Series Preferred Stock outstanding at March 31, 2012, March 31, 2011 and December 31, 2011, respectively. There were 9,696, 9,742 and 9,696 shares of Fitchburg's 8.00% Series Preferred Stock outstanding at March 31, 2012, March 31, 2011 and December 31, 2011, respectively.

There was less than $0.1 million of total dividends declared on Preferred Stock in each of the three month periods ended March 31, 2012 and March 31, 2011, respectively.

- Definition

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph d

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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 1
-Section B
-Paragraph 7, 11A
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 3, 4, 5, 6, 7, 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Article 4

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Number 5
-Paragraph 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

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-Number Topic 4
-Section C

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

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+ Details

Long-Term Debt, Credit Arrangements And Guarantees

3 Months Ended

Mar. 31, 2012

Long-Term Debt, Credit Arrangements And Guarantees [Abstract]

Long-Term Debt, Credit Arrangements And Guarantees

NOTE 4 – LONG-TERM DEBT, CREDIT ARRANGEMENTS AND GUARANTEES

Long-Term Debt

Details on long-term debt at March 31, 2012, March 31, 2011 and December 31, 2011 are shown below ($ Millions):


	March 31,				December 31,
	2012		2011		2011
Unitil Corporation Senior Notes:
6.33% Notes, Due May 1, 2022	$	20.0	$	20.0	$	20.0

Unitil Energy Systems, Inc.:
First Mortgage Bonds:
5.24% Series, Due March 2, 2020		15.0		15.0		15.0
8.49% Series, Due October 14, 2024		15.0		15.0		15.0
6.96% Series, Due September 1, 2028		20.0		20.0		20.0
8.00% Series, Due May 1, 2031		15.0		15.0		15.0
6.32% Series, Due September 15, 2036		15.0		15.0		15.0

Fitchburg Gas and Electric Light Company:
Long-Term Notes:
6.75% Notes, Due November 30, 2023		19.0		19.0		19.0
7.37% Notes, Due January 15, 2029		12.0		12.0		12.0
7.98% Notes, Due June 1, 2031		14.0		14.0		14.0
6.79% Notes, Due October 15, 2025		10.0		10.0		10.0
5.90% Notes, Due December 15, 2030		15.0		15.0		15.0

Northern Utilities Senior Notes:
6.95% Senior Notes, Series A, Due December 3, 2018		30.0		30.0		30.0
5.29% Senior Notes, Due March 2, 2020		25.0		25.0		25.0
7.72% Senior Notes, Series B, Due December 3, 2038		50.0		50.0		50.0

Granite State Senior Notes:
7.15% Senior Notes, Due December 15, 2018		10.0		10.0		10.0

Unitil Realty Corp.:
Senior Secured Notes:
8.00% Notes, Due Through August 1, 2017		3.2		3.7		3.3

Total Long-Term Debt		288.2		288.7		288.3
Less: Current Portion		0.5		0.5		0.5

Total Long-term Debt, Less Current Portion	$	287.7	$	288.2	$	287.8

The fair value of the Company's long-term debt is estimated based on the quoted market prices for the same or similar issues, or on the current rates offered to the Company for debt of the same remaining maturities. The fair value of the Company's long-term debt at March 31, 2012 is estimated to be approximately $336 million, before considering any costs, including prepayment costs, to market the Company's debt. Currently, the Company believes that there is no active market in the Company's debt securities, which have all been sold through private placements.

Credit Arrangements

Unitil has a revolving credit facility with a group of banks that extends to October 8, 2013. The borrowing limit under the revolving credit facility was $115.0 million at March, 31, 2012, $80.0 million at March 31, 2011 and $115.0 million at December 31, 2011. There were $77.6 million, $50.6 million and $87.9 million in short-term debt outstanding through bank borrowings under the revolving credit facility at March 31, 2012, March 31, 2011 and December 31, 2011, respectively. The total amount of credit available under the Company's revolving credit facility was $37.4 million, $29.4 million and $27.1 million at March 31, 2012, March 31, 2011 and December 31, 2011, respectively. The revolving credit facility contains customary terms and conditions for credit facilities of this type, including, without limitation, covenants restricting the Company's ability to incur liens, merge or consolidate with another entity or change its line of business. The revolving credit agreement also contains a covenant restricting the Company's ability to permit funded debt to exceed 65% of capitalization at the end of each fiscal quarter. As of March 31, 2012, March 31, 2011 and December 31, 2011, the Company was in compliance with the financial covenants contained in the revolving credit agreement.

Northern Utilities enters into asset management agreements under which Northern Utilities releases certain natural gas pipeline and storage assets, resells the natural gas storage inventory to an asset manager and subsequently repurchases the inventory over the course of the natural gas heating season at the same price at which it sold the natural gas inventory to the asset manager. There were $6.3 million, $1.8 million and $14.9 million outstanding at March 31, 2012, March 31, 2011 and December 31, 2011, respectively, related to these asset management agreements. The amount of natural gas inventory released in March 2012, which is payable in April 2012, is $0.3 million and recorded in Accounts Payable at March 31, 2012. The amount of natural gas inventory released in March 2011, which was payable in April 2011, is $1.7 million and recorded in Accounts Payable at March 31, 2011. The amount of natural gas inventory released in December 2011, which was payable in January 2012, is $2.5 million and recorded in Accounts Payable at December 31, 2011.

Guarantees

The Company also provides limited guarantees on certain energy and natural gas storage management contracts entered into by the distribution utilities. The Company's policy is to limit the duration of these guarantees. As of March 31, 2012, there were approximately $31.6 million of guarantees outstanding and the longest term guarantee extends through February 2014.

The Company also guarantees the payment of principal, interest and other amounts payable on the notes issued by Unitil Realty and Granite State. As of March 31, 2012, the principal amount outstanding for the 8% Unitil Realty notes was $3.2 million. On December 15, 2008, the Company entered into a guarantee for the payment of principal, interest and other amounts payable on the $10 million Granite State notes due 2018. As of March 31, 2012, the principal amount outstanding for the 7.15% Granite State notes was $10.0 million.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References + Details

Regulatory Matters	3 Months Ended
Regulatory Matters	Mar. 31, 2012
Regulatory Matters [Abstract]
Regulatory Matters	NOTE 6 – REGULATORY MATTERS UNITIL'S REGULATORY MATTERS ARE DESCRIBED IN NOTE 5 TO THE FINANCIAL STATEMENTS IN ITEM 8 OF PART II OF UNITIL CORPORATION'S FORM 10-K FOR DECEMBER 31, 2011 AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON FEBRUARY 1, 2012. Regulatory Matters Fitchburg – Increase in Base Rates Approved – On August 1, 2011, the Massachusetts Department of Public Utilities (MDPU) issued an order approving increases of $3.3 million and $3.7 million in annual distribution revenues for Fitchburg's electric and gas divisions, respectively. The MDPU also approved revenue decoupling mechanisms and a return on equity of 9.2% for both the electric and gas divisions of Fitchburg. The rate increase for Fitchburg's electric division included the recovery of $11.4 million of previously deferred emergency storm restoration costs associated with the December 2008 ice storm, which costs are to be amortized and recovered over seven (7) years without carrying costs. The order provides resolution to the open regulatory matters concerning the ratemaking treatment and cost recovery related to the December 2008 ice storm event. Granite State – Increase in Base Rates Approved – On January 31, 2011, the FERC approved a settlement agreement providing for an increase of $1.7 million in annual revenue, based on new gas transportation rates to be effective January 1, 2011. Subsequently, on August 31, 2011, the FERC approved an amendment to the settlement agreement which provides for an additional increase of approximately $0.5 million in Granite State's annual revenues effective August 1, 2011. Under the amended settlement agreement, beginning in 2012, Granite State is permitted to file incremental annual rate adjustment filings to recover the revenue requirements for certain specified future capital cost additions to transmission plant projects totaling up to $11.4 million. Of the $11.4 million, $1.6 million has been expended and is being recovered in the 2011 approved rates. The annual rate adjustments would be effective August 1 of each year, and are projected to conclude in 2014 when the major projects will be completed. The annual revenue increases for these rate adjustments are estimated to be approximately $0.5 million each year during 2012 through 2014. Unitil Energy – Increase in Base Rates Approved – On April 26, 2011, the New Hampshire Public Utilities Commission (NHPUC) approved a final rate settlement which makes permanent a temporary increase of $5.2 million in annual revenue effective July 1, 2010, and provides for an additional increase of $5.0 million in annual revenue effective May 1, 2011. The settlement extends through May 1, 2016 and provides for a long-term rate plan and earnings sharing mechanism, with estimated future increases of $1.5 million to $2.0 million in annual revenue to occur on May 1, 2012, May 1, 2013 and May 1, 2014, to support Unitil Energy's continued capital improvements to its distribution system. The rate plan allows Unitil to file for additional rate relief if its return on equity is less than 7% and a sharing of earnings with customers if its return on equity is greater than 10% in a calendar year. The settlement provides for a return on equity of 9.67%, a common equity ratio of 45.45% and an overall weighted cost of capital of 8.39% to determine changes to distribution rate levels. The settlement approved Unitil Energy's proposal for an augmented vegetation management program and reliability enhancement program. Under the augmented vegetation management program, Unitil Energy will be increasing its vegetation management spending from a test-year spending level of approximately $0.7 million to $3.1 million per year by 2013. Under the new reliability enhancement program, Unitil Energy will spend $1.8 million annually towards targeted projects designed to enhance system reliability. The funding for both of these programs is included in the future rate increases discussed above. The settlement provides for recovery of deferred December 2008 ice storm and February 2010 wind storm costs of approximately $7.6 million, including carrying charges. These costs will be recovered over eight years in the form of a tariff surcharge. Finally, the settlement establishes a major storm reserve of $400,000 annually, which will be used to recover costs associated with responding to and recovering from future qualifying major storm events. Unitil Energy filed its first step adjustment filing on February 29, 2012 for implementation on May 1, 2012, which includes rate increases to recover the increased spending for its vegetation management program and reliability enhancement program discussed above. The adjustment filing remains pending. Northern Utilities – Increase in Base Rates Approved, Settlement Reached – In May 2011, Northern Utilities filed two separate rate cases with the NHPUC and Maine Public Utilities Commission (MPUC) requesting approval to increase its natural gas distribution base rates in New Hampshire and Maine, respectively. On November 29, 2011, the MPUC approved a comprehensive settlement agreement providing for a $7.8 million permanent increase in annual distribution revenue for Northern Utilities' Maine operations, effective January 1, 2012, and an additional permanent increase in annual distribution revenue of $0.85 million to recover the costs of 2011 cast iron pipe replacement capital spending effective May 1, 2012. The settlement is inclusive of an earlier settlement for a temporary rate increase of $3.5 million in annual distribution revenue effective November 1, 2011. The settlement also precludes Northern Utilities from filing for a new base rate increase with an effective date prior to January 1, 2014. On March 22, 2012, Northern Utilities, the Staff of the NHPUC and the Office of Consumer Advocate agreed to a settlement agreement providing for a $3.7 million permanent increase in annual revenues, effective May 1, 2012. Previously, on July 22, 2011, the NHPUC approved a settlement for a temporary rate increase of approximately $1.7 million in annual revenue effective August 1, 2011. A hearing was held on March 29, 2012, and the NHPUC issued an order approving the settlement agreement on April 24, 2012. Permanent rates will be reconciled back to August 1, 2011. Fitchburg – Management Audit – On September 1, 2011, the MDPU issued its order with respect to a comprehensive independent management audit of Fitchburg's management practices, undertaken as a result of the MDPU's investigation of Fitchburg's response to the December 2008 ice storm. The audit report found Fitchburg's management practices to be comprehensive, sound and in-line with industry practice. The MDPU accepted the majority of the audit report, and required the Company to implement several of the report's recommendations, as well as provide semi-annual status updates as to the Company's implementation progress. The Company filed status reports with the MDPU on September 30, 2011 and March 30, 2012. Fitchburg – Electric Operations – On November 30, 2011, Fitchburg submitted its annual reconciliation of costs and revenues for transition and transmission under its restructuring plan. The filing includes the reconciliation of costs and revenues for a number of surcharges and cost factors which are under individual review in separate proceedings before the MDPU, including the Pension/PBOP Adjustment, Residential Assistance Adjustment Factor, Net Metering Recovery Surcharge, Attorney General Consultant Expense Factor and Revenue Decoupling Adjustment Factor. The rates were approved effective January 1, 2012, subject to reconciliation pending investigation by the MDPU. This matter remains pending. Final orders on Fitchburg's 2009 and 2010 annual reconciliation filings also remain pending. Fitchburg – Gas Operations – On November 2, 2011, the Massachusetts Supreme Judicial Court (SJC) issued its decision vacating an MDPU order issued on November 2, 2009 which had ordered Fitchburg to refund $4.6 million of natural gas costs, plus interest. The SJC ordered instead, a $0.2 million refund, plus interest. The Company had previously recorded a pre-tax charge to earnings and recognized a Regulatory Liability of $4.9 million in the fourth quarter of 2009 based on the MDPU's original order. As a result of the decision, the Regulatory Liability was adjusted and the Company recognized a credit of $4.7 million in the fourth quarter of 2011. The Company began the recoupment of the amounts previously refunded, with interest, effective January 1, 2012. In order to minimize the rate impact on customers, the recoupment is scheduled to occur over three consecutive heating seasons, beginning January 1, 2012. Fitchburg – Storm Cost Deferral Petition – On December 16, 2011, Fitchburg filed a request with the MDPU for authorization to defer, for future recovery in rates, the costs incurred to perform storm-related emergency repairs on its electric distribution system as a result of two recent storms, Tropical Storm Irene, which occurred on August 28, 2011, and a severe snow storm, which occurred on October 29-30, 2011. Fitchburg estimates that, including capitalized amounts, it incurred $1.5 million in costs for Tropical Storm Irene and $3.3 million in costs for the October 2011 snow storm. The Company has requested approval to defer and accrue carrying charges on approximately $4.3 million of the storm costs that were not capitalized into utility plant. This matter remains pending before the MDPU. Fitchburg – Service Quality – On March 1, 2012, Fitchburg submitted its 2011 Service Quality Reports for both its gas and electric divisions. Fitchburg reported that it met or exceeded its benchmarks for service quality performance in all metrics for both its gas and electric divisions. On January 13, 2012, the MDPU issued its order approving the 2010 Service Quality Report for Fitchburg's gas division. The 2010 Service Quality report for Fitchburg's electric division remains pending. Unitil Energy – 2011 Storm Costs – On December 16, 2011, Unitil Energy filed a petition with the NHPUC to increase its storm recovery adjustment factor effective May 1, 2012. The increase would allow the Company to recover the approximately $4.4 million of costs of repairing damage to its electrical system resulting from the August 2011 Tropical Storm Irene and the October 2011 snow storm. The NHPUC Staff audited the costs and filed a memorandum with the NHPUC recommending that the costs be recovered by the Company over a five year period with carrying costs of 4.52%, subject to a full reconciliation of all costs recovered. Unitil Energy accepts and supports the Staff recommendation. On April 24, 2012, the NHPUC issued an order approving the recommendation of the Staff. Unitil Energy – Billing Adjustment – In August 2011, Unitil Energy and one of its larger customers in New Hampshire entered into an agreement regarding a billing error that resulted from a transformer connected to the customer's meter, which had been mislabeled by the manufacturer, and caused Unitil Energy to overcharge the customer for bills issued from October 2004 through January 2011. The amount of the customer's overpayment was calculated to be $1.8 million. As a result of the settlement, Unitil Energy reimbursed the customer $1.8 million plus $0.3 million of interest. The Company recognized a non-recurring charge of $0.4 million for distribution charges plus interest in 2011. As a result of this metering issue, which was discovered in February 2011, certain other customers in the Company's service areas were under-billed from October 2004 through January 2011 for supply-related charges. Accordingly, the Company has requested authorization from the NHPUC to adjust reconciling account balances and process the billing correction. The Company's request remains pending before the NHPUC. Unitil Energy – Annual Rate Reconciliation Filing – On July 29, 2011, the NHPUC approved Unitil Energy's annual reconciliation and rate filing under its restructuring plan, for rates effective August 1, 2011, including reconciliation of prior year costs and revenues. Northern Utilities – Cast Iron Pipe Replacement Program – On July 30, 2010, the MPUC approved a settlement agreement providing for an accelerated replacement program for cast iron distribution pipe remaining in portions of Northern Utilities' Maine service areas. Under the agreement, Northern Utilities will proceed with a comprehensive upgrade and replacement program (the Program), which will provide for the systematic replacement of cast iron, wrought iron and bare steel pipe in Northern Utilities' natural gas distribution system in Portland and Westbrook, Maine and the conversion of the system to intermediate pressure. The agreement establishes the objective of completing the Program by the end of the 2024 construction season. Unitil Corporation – FERC Audit – On November 3, 2011, the FERC commenced an audit of Unitil Corporation, including its associated service company and its electric and natural gas distribution companies. Among other requirements, the audit will evaluate the Company's compliance with: i) cross-subsidization restrictions on affiliate transactions; ii) regulations under the Energy Policy Act of 2005; and the iii) uniform system of accounts for centralized service companies. The Company expects the final audit report will be issued in August, 2012. Legal Proceedings The Company is involved in legal and administrative proceedings and claims of various types, which arise in the ordinary course of business. The Company believes, based upon information furnished by counsel and others, that the ultimate resolution of these claims will not have a material impact on the Company's financial position. A putative class action complaint was filed against Fitchburg on January 7, 2009 in Worcester Superior Court in Worcester, Massachusetts, captioned Bellerman v. Fitchburg Gas and Electric Light Company. On April 1, 2009, an Amended Complaint was filed in Worcester Superior Court and served on Fitchburg. The Amended Complaint seeks an unspecified amount of damages, including the cost of temporary housing and alternative fuel sources, emotional and physical pain and suffering and property damages allegedly incurred by customers in connection with the loss of electric service during the ice storm in Fitchburg's service areas in December, 2008. The Amended Complaint includes M.G.L. ch. 93A claims for purported unfair and deceptive trade practices related to the December 2008 ice storm. On September 4, 2009, the Superior Court issued its order on the Company's Motion to Dismiss the Complaint, granting it in part and denying it in part. The Company anticipates that the court will decide whether the lawsuit is appropriate for class action treatment in late 2012. The Company continues to believe the suit is without merit and will defend itself vigorously. On November 2, 2011, the Massachusetts Supreme Judicial Court (SJC) issued its decision vacating an order issued on November 2, 2009 by the MDPU in which the MDPU ordered Fitchburg to refund $4.6 million of natural gas costs, plus interest. The MDPU's original order issued in 2009 found that the Company had engaged in certain price stabilization practices for the 2007 / 2008 and 2008 / 2009 heating seasons without the MDPU's prior approval and that the Company's natural gas purchasing practices were imprudent. The Company appealed the MDPU's decision to the SJC. The SJC's decision vacates the MDPU's order to refund $4.6 million, plus interest, in favor of a $0.2 million refund, plus interest. See additional discussion above in Regulatory Matters.

Retirement Benefit Obligations

3 Months Ended

Mar. 31, 2012

Retirement Benefit Obligations [Abstract]

Retirement Benefit Obligations

NOTE 9: RETIREMENT BENEFIT OBLIGATIONS

The Company co-sponsors the Unitil Corporation Retirement Plan (Pension Plan), the Unitil Retiree Health and Welfare Benefits Plan (PBOP Plan), and the Unitil Corporation Supplemental Executive Retirement Plan (SERP) to provide certain pension and postretirement benefits for its retirees and current employees. Please see Note 9 to the Consolidated Financial Statements in the Company's Form 10-K for the year ended December 31, 2011 as filed with the SEC on February 1, 2012 for additional information regarding these plans.

The following table includes the key weighted average assumptions used in determining the Company's benefit plan costs and obligations:


	2012			2011
Used to Determine Plan Costs
Discount Rate		4.60	%		5.35	%
Rate of Compensation Increase		3.00	%		3.50	%
Expected Long-term rate of return on plan assets		8.50	%		8.50	%
Health Care Cost Trend Rate Assumed for Next Year		6.50	%		7.00	%
Ultimate Health Care Cost Trend Rate		4.00	%		4.00	%
Year that Ultimate Health Care Cost Trend Rate is reached		2017			2017

The following table provides the components of the Company's Retirement plan costs ($000's):


	Pension Plan						PBOP Plan						SERP
Three Months Ended March 31,	2012			2011			2012			2011			2012		2011
Service Cost	$	807		$	735		$	517		$	479		$	72	$	71
Interest Cost		1,158			1,171			576			570			53		57
Expected Return on Plan Assets		(1,347	)		(1,210	)		(174	)		(204	)		—		—
Prior Service Cost Amortization		47			62			432			432			3		3
Transition Obligation Amortization		—			—			5			5			—		—
Actuarial Loss Amortization		904			783			32			—			16		19

Sub-total		1,569			1,541			1,388			1,282			144		150
Amounts Capitalized and Deferred		(557	)		(503	)		(420	)		(234	)		—		—

Net Periodic Benefit Cost Recognized	$	1,012		$	1,038		$	968		$	1,048		$	144	$	150

Employer Contributions

As of March 31, 2012, the Company had made $4.8 million of contributions to its Pension Plan in 2012. The Company, along with its subsidiaries, expects to continue to make contributions to its Pension Plan in 2012 and future years at minimum required and discretionary funding levels consistent with the amounts recovered in the distribution utilities' rates for these Pension Plan costs.

As of March 31, 2012, the Company had made $13,000 of contributions to the SERP Plan in 2012. The Company presently anticipates contributing an additional $40,000 to the SERP Plan in 2012.

- Definition

The entire disclosure for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph h
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph q
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 8
-Subparagraph m
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 106
-Paragraph 518
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 03-2
-Paragraph 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 30
-Paragraph 26
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 20, 21, 22
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7, 21, 22
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 6, 7, 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Implementation Guide (Q and A)
-Number FAS88
-Paragraph 63
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

+ Details

Environmental Matters	3 Months Ended
Environmental Matters	Mar. 31, 2012
Environmental Matters [Abstract]
Environmental Matters	NOTE 7 – ENVIRONMENTAL MATTERS UNITIL'S ENVIRONMENTAL MATTERS ARE DESCRIBED IN NOTE 5 TO THE FINANCIAL STATEMENTS IN ITEM 8 OF PART II OF UNITIL CORPORATION'S FORM 10-K FOR DECEMBER 31, 2011 AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON FEBRUARY 1, 2012. The Company's past and present operations include activities that are generally subject to extensive and complex federal and state environmental laws and regulations including laws and regulations related to pipeline safety. The Company believes it is in substantial compliance with applicable environmental, health and safety laws and regulations, and the Company believes that as of March 31, 2012, there were no material losses reasonably likely to be incurred in excess of recorded amounts. However, there can be no assurance that significant costs and liabilities will not be incurred in the future. It is possible that other developments, such as increased stringent federal, state or local environmental health and safety laws and regulations, could result in increased compliance costs that we cannot currently quantify and that affect our operations. Fitchburg is in the process of developing long-range plans for a feasible permanent remediation solution of a former manufactured gas plant (MGP) site at Sawyer Passway, located in Fitchburg, Massachusetts, including alternatives for re-use of the site. Included in Environmental Obligations on the Company's unaudited Consolidated Balance Sheet at March 31, 2012 are accrued liabilities totaling $12.0 million related to estimated future cleanup costs for permanent remediation of the Sawyer Passway site. The amounts recorded do not assume any amounts are recoverable from insurance companies or other third parties. Fitchburg recovers the environmental response costs incurred at this former MGP site in gas rates pursuant to the terms of a cost recovery agreement approved by the MDPU. Pursuant to this agreement, Fitchburg is authorized to amortize and recover environmental response costs from gas customers over succeeding seven-year periods, without carrying costs. Fitchburg had filed suit against several of its former insurance carriers seeking coverage for past and future environmental response costs at the site. In January 2011, Fitchburg settled with the remaining insurance carriers for approximately $2.0 million and received these payments in the first quarter of 2011. Any recovery that Fitchburg receives from insurance or third-parties with respect to environmental response costs, net of the unrecovered costs associated therewith, are shared equally between Fitchburg and its gas customers. Also included in Environmental Obligations on the Company's Consolidated Balance Sheet at March 31, 2012 are accrued liabilities totaling $2.5 million associated with Northern Utilities' environmental remediation obligations for former MGP sites. In addition to the amounts noted above, there are $0.2 million of accrued liabilities in Other Current Liabilities on the Company's Consolidated Balance Sheet at March 31, 2012 associated with Northern Utilities' environmental remediation obligations for former MGP sites. Corresponding Regulatory Assets were recorded to reflect that the future recovery of these environmental remediation costs is expected based on regulatory precedent and established practices. The Company's ultimate liability for future environmental remediation costs, including MGP site costs, may vary from estimates, which may be adjusted as new information or future developments become available. Based on the Company's current assessment of its environmental responsibilities, existing legal requirements and regulatory policies, the Company does not believe that these environmental costs will have a material adverse effect on the Company's consolidated financial position or results of operations. It is possible that other developments, such as increased stringent federal, state or local environmental health and safety laws and regulations, could result in increased compliance costs that we cannot currently quantify.

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2012
Income Taxes [Abstract]
Income Taxes	NOTE 8: INCOME TAXES The Company bills its customers for sales tax in Massachusetts and Maine and consumption tax in New Hampshire. These taxes are remitted to the appropriate departments of revenue in each state and are excluded from revenues on the Company's unaudited Consolidated Statements of Earnings. As of December 31, 2011, the Company had recorded cumulative federal and state net operating loss (NOL) carryforward assets of $11.7 million to offset against taxes payable in future periods. If unused, the Company's state NOL carryforward assets will begin to expire in 2019 and the federal NOL carryforward assets will begin to expire in 2029. In addition, at December 31, 2011, the Company had $1.4 million of Alternative Minimum Tax (AMT) credit carryforwards to offset future AMT taxes payable indefinitely. According to Internal Revenue Code rules, NOL refunds in excess of $2.0 million fall under the jurisdiction of the Joint Committee of Congress (Joint Committee) and are subject to review by the IRS and attorneys of the Joint Committee. As a result, the Company, on April 1, 2011, received notice that its federal income tax return filing for the year ended December 31, 2009 would be under examination by the IRS. The IRS is currently performing field work as part of their audit procedures. In addition, because of the application of the 2009 NOL, tax periods ended December 31, 2004, 2005 and 2007 are subject to examination to the extent of the application of the NOL to those periods. The Company believes that the ultimate resolution of this examination will not have a material impact on the Company's consolidated financial position or results of operations. The Company evaluated its tax positions at December 31, 2011 and for the current interim reporting period ended March 31, 2012 in accordance with the FASB Codification, and has concluded that no adjustment for recognition, derecognition, settlement and foreseeable future events to any unrecognized tax liabilities or assets as defined by the FASB Codification is required. The Company does not have any unrecognized tax positions for which it is reasonably possible that the total amounts recognized will significantly change within the next 12 months. The Company remains subject to examination by Federal, Maine, Massachusetts, and New Hampshire tax authorities for the tax periods ended December 31, 2008; December 31, 2009; and December 31, 2010.