Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 8,197	$ 30,343
Restricted cash	245,100	0
Accounts receivable:
Trade, net of allowance for bad debt of $362 and $405, respectively	37,258	22,680
Accrued revenue and other	103,622	143,197
Fair value of derivative assets	6,680	2,867
Natural gas and natural gas liquids, prepaid expenses and other	22,874	9,965
Total current assets	423,731	209,052
Property and equipment, net of accumulated depreciation of $446,333 and $406,773, respectively	1,286,918	1,242,890
Fair value of derivative assets	1,604
Intangible assets, net of accumulated amortization of $224,729 and $199,248, respectively	425,981	451,462
Investment in limited liability company	87,250	35,000
Other assets, net	22,953	24,212
Total assets	2,248,437	1,962,616
Current liabilities:
Accounts payable, drafts payable, and other	27,886	22,549
Accrued gas purchases	76,787	106,233
Fair value of derivative liabilities	2,839	5,587
Current portion of long-term debt	250,000
Other current liabilities	46,020	66,567
Accrued interest	27,036	24,918
Total current liabilities	430,568	225,854
Long-term debt	762,357	798,409
Other long-term liabilities	22,383	23,919
Deferred tax liability	78,394	85,187
Fair value of derivative liabilities	7
Commitments and contingencies
Stockholders Equity	954,728	829,247
Total liabilities and stockholders' equity	$ 2,248,437	$ 1,962,616

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).