Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 26,790	$ 30,343
Accounts receivable:
Trade, net of allowance for bad debt of $210 and $405, respectively	12,352	22,680
Accrued revenue and other	118,579	143,197
Fair value of derivative assets	1,274	2,867
Natural gas and natural gas liquids, prepaid expenses and other	16,352	9,965
Total current assets	175,347	209,052
Property and equipment, net of accumulated depreciation of $426,227 and $406,773, respectively	1,252,271	1,242,890
Fair value of derivative assets	131	0
Intangible assets, net of accumulated amortization of $211,975 and $199,248, respectively	438,734	451,462
Investment in limited liability company	39,860	35,000
Other assets, net	24,206	24,212
Total assets	1,930,549	1,962,616
Current liabilities:
Accounts payable, drafts payable, and other	16,389	22,549
Accrued gas purchases	80,203	106,233
Fair value of derivative liabilities	4,843	5,587
Other current liabilities	47,444	66,567
Accrued interest	8,991	24,918
Total current liabilities	157,870	225,854
Long-term debt	852,883	798,409
Other long-term liabilities	23,156	23,919
Deferred tax liability	84,605	85,187
Fair value of derivative liabilities	110	0
Commitments and contingencies
Stockholders Equity	811,925	829,247
Total liabilities and stockholders' equity	$ 1,930,549	$ 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).