Derivative Insturments and Hedging Activities (Policies)	6 Months Ended
	Jun. 30, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives, Policy	These natural gas price swaps are accounted for as economic hedges, with changes in their fair value recorded to Deferred natural gas purchases. The Company is exposed to certain risks in its ongoing business operations. The primary risks managed by using derivative instruments are interest rate risk and commodity price risk. Interest rate swaps and treasury rate locks are the principal derivative instruments used by the Company to manage interest rate risk associated with its long-term borrowings, although other interest rate derivative contracts may also be used from time to time. Natural gas and NGL price swaps and NGL processing spread swaps are the principal derivative instruments used by the Company to manage commodity price risk associated with purchases and/or sales of natural gas and/or NGL, although other commodity derivative contracts may also be used from time to time. The Company recognizes all derivative instruments as assets or liabilities at fair value in the unaudited interim Condensed Consolidated Balance Sheet. During the predecessor periods, these treasury rate locks were accounted for as cash flow hedges, with the effective portion of their settled value recorded in Accumulated other comprehensive income and reclassified into Interest expense in the same periods during which the related interest payments on long-term debt impact earnings. These natural gas price swaps are accounted for as cash flow hedges, with the effective portion of changes in their fair value recorded in Accumulated other comprehensive income and reclassified into Operating revenues in the same periods during which the forecasted natural gas sales impact earnings. These interest rate swaps were accounted for as cash flow hedges, with the effective portion of changes in their fair value recorded in Accumulated other comprehensive income and reclassified into Interest expense in the same periods during which the related interest payments on long-term debt impacted earnings. These NGL price swaps are accounted for as cash flow hedges, with the effective portion of changes in their fair value recorded in Accumulated other comprehensive income and reclassified into Operating revenues in the same periods during which the forecasted NGL sales impact earnings.

Disclosure of accounting policy for its derivative instruments and hedging activities. Disclosure may include: (1) Each method used to account for derivative financial instruments and derivative commodity instruments ("derivatives"); (2) the types of derivatives accounted for under each method; (3) the criteria required to be met for each accounting method used, including a discussion of the criteria required to be met for hedge or deferral accounting and accrual or settlement accounting (for example, whether and how risk reduction, correlation, designation, and effectiveness tests are applied); (4) the accounting method used if the criteria specified for hedge accounting are not met; (5) the method used to account for termination of derivatives designated as hedges or derivatives used to affect directly or indirectly the terms, fair values, or cash flows of a designated item; (6) the method used to account for derivatives when the designated item matures, is sold, is extinguished, or is terminated. In addition, the method used to account for derivatives designated to an anticipated transaction, when the anticipated transaction is no longer likely to occur; and (7) where and when derivatives, and their related gains or losses are reported in the statement of financial position, cash flows, and results of operations and (8) an accounting policy decision to offset fair value amounts with counterparties. An entity may also describe its embedded derivatives, and the method(s) used to determine the fair values of derivatives and any significant assumptions used in such valuations.

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+ Details