CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income	$ 218,788	$ 106,245	$ 31,102
Adjustments to reconcile net income to net cash provided by operating activities (net of acquisitions):
Depreciation	189,549	149,954	123,198
Amortization of intangible assets	53,320	43,617	40,833
Loss on redemption of debt		78,996	46,326
Amortization of deferred financing costs and discount	5,601	5,114	10,264
Accretion of asset retirement obligations	677	1,190	237
Amortization of deferred contract cost	312	312	312
Phantom unit compensation expense	14,615	13,479	15,319
Equity in (earnings) loss of unconsolidated affiliates	(699)	1,095	(1,562)
Contribution to unconsolidated affiliate		(560)
Distributions from unconsolidated affiliate	2,600	300	2,508
Unrealized (gain) loss on derivative instruments	(102,127)	4,147	28,475
Loss on disposal of property, plant and equipment	6,254	8,797	3,149
Deferred income taxes	40,694	(3,929)	(4,466)
Other		1,626
Changes in operating assets and liabilities, net of working capital acquired:
Receivables	32,588	(45,463)	(37,090)
Inventories	16,580	(16,025)	5,710
Other current assets	(23,115)	(3,728)	2,654
Accounts payable and accrued liabilities	28,412	54,745	45,361
Other long-term assets	(647)	(307)	174
Other long-term liabilities	13,311	15,093	(176)
Net cash provided by operating activities	496,713	414,698	312,328
Cash flows from investing activities:
Restricted cash	(9,497)	2,006	(28,001)
Capital expenditures	(1,951,427)	(551,281)	(458,668)
Acquisition of business, net of cash acquired	(506,797)	(230,728)
Investment in unconsolidated affiliate	(5,227)
Proceeds from disposal of property, plant and equipment	596	3,450	733
Net cash flows used in investing activities	(2,472,352)	(776,553)	(485,936)
Cash flows from financing activities:
Proceeds from public equity offerings, net	1,634,081	1,095,488	142,255
Proceeds from Credit facility	511,100	1,182,200	494,404
Payments of Credit facility	(577,100)	(1,116,200)	(553,704)
Proceeds from long-term debt	742,613	1,199,000	500,000
Payments of long-term debt		(693,888)	(375,000)
Payments of premiums on redemption of long-term debt		(71,377)	(9,732)
Payments for debt issuance costs, deferred financing costs and registration costs	(14,720)	(20,163)	(20,912)
Acquisition of non-controlling interest, including transaction costs		(997,601)
Contributions from non-controlling interest	265,620	126,392	158,293
Payments of SMR Liability	(2,058)	(1,875)	(1,354)
Cash paid for taxes related to net settlement of share-based payment awards	(8,067)	(6,354)	(3,834)
Excess tax benefits related to share-based compensation	907	1,084	98
Payment of distributions to common unitholders	(339,967)	(218,398)	(181,058)
Payment of distributions to non-controlling interest	(5,887)	(66,887)	(6,150)
Net cash flows provided by financing activities	2,206,522	411,421	143,306
Net increase (decrease) in cash and cash equivalents	230,883	49,566	(30,302)
Cash and cash equivalents at beginning of year	117,016	67,450	97,752
Cash and cash equivalents at end of year	$ 347,899	$ 117,016	$ 67,450