Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Cash flows from operating activities:
Net income	$ (13,986)	$ (144)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	110,163	93,257
(Gain) loss on sale of property and other assets	(3,381)	317
Deferred tax benefit	(4,492)	(3,703)
Non-cash stock-based compensation	7,695	5,688
Non-cash portion of derivatives (gain) loss	(5,523)	165
Amortization of debt issue costs	3,940	5,278
Amortization of discount on notes	1,423	1,423
Earnings from equity investment in limited liability company	(1,511)	0
Changes in assets and liabilities:
Accounts receivable, accrued revenue and other	(18,276)	30,156
Natural gas and natural gas liquids, prepaid expenses and other	(7,145)	(3,468)
Accounts payable, accrued gas and crude oil purchases	(26,029)	(46,815)
Net cash provided by operating activities	42,878	82,154
Cash flows from investing activities:
Additions to property and equipment	(141,319)	(62,829)
Acquisition	(212,521)	0
Proceeds from sale of property	11,677	425
Investment in limited liability company	(52,250)	(35,000)
Net cash used in investing activities	(394,413)	(97,404)
Cash flows from financing activities:
Proceeds from borrowings	696,500	390,250
Payments on borrowings	(526,000)	(322,308)
Payments on capital lease obligations	(2,337)	(2,254)
Increase (decrease) in drafts payable	4,319	(103)
Debt refinancing costs	(6,896)	(3,936)
Conversion of restricted stock, net of shares withheld for taxes	(794)	(1,066)
Distributions to non-controlling partners in the Partnership	(52,536)	(42,753)
Common dividends	(17,078)	(13,025)
Issuance of common units by the Partnership	232,791
Conversion of restricted units, net of units withheld for taxes	(1,030)	(1,798)
Proceeds from exercise of Partnership unit options	348	513
Net cash provided by financing activities	327,287	3,520
Net decrease in cash and cash equivalents	(24,248)	(11,730)
Cash and cash equivalents, beginning of period	30,343	22,780
Cash and cash equivalents, end of period	6,095	11,050
Cash paid for interest	70,460	70,074
Cash paid for income taxes	$ 953	$ 905