Supplemental Condensed Consolidating Financial Information (Details 3) (USD $) In Thousands, unless otherwise specified	0 Months Ended										1 Months Ended	12 Months Ended
	Nov. 19, 2012	Aug. 17, 2012	May 14, 2012	Mar. 16, 2012	Jan. 13, 2012	Dec. 19, 2011	Oct. 13, 2011	Jul. 13, 2011	Jan. 14, 2011	Apr. 06, 2010	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Condensed Consolidating Statements of Cash Flows
Net cash (used in) 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 affiliates												(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	437,000	338,000	427,000	388,000	38,000	521,000	251,000	185,000	138,000	142,000	6,000	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 issue costs and deferred financing costs												(14,720)	(20,163)	(20,912)
Acquisition of non-controlling interest, including transaction costs													(997,601)
Contribution from non-controlling interest												265,620	126,392	158,293
Share-based payment activity												(7,160)	(5,270)	(3,736)
Payment of distributions												(345,854)	(285,285)	(187,208)
Payments of SMR Liability												(2,058)	(1,875)	(1,354)
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	347,899	117,016	67,450
Parent
Condensed Consolidating Statements of Cash Flows
Net cash (used in) provided by operating activities												(154,328)	(126,782)	(102,042)
Cash flows from investing activities:
Capital expenditures												(138)	(789)	(1,924)
Equity investments												(55,283)	(47,295)	(44,346)
Distributions from consolidated affiliates												75,431	50,718	41,167
Investment in intercompany notes, net												(12,300)	(37,990)	12,350
Net cash flows used in investing activities												7,710	(35,356)	7,247
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 issue costs and deferred financing costs												(14,720)	(20,163)	(20,912)
Acquisition of non-controlling interest, including transaction costs													(997,601)
Share-based payment activity												(8,067)	(6,354)	(3,834)
Payment of distributions												(339,967)	(218,398)	(181,058)
Intercompany advances, net												(1,591,329)	(190,547)	102,376
Net cash flows provided by financing activities												356,611	162,160	94,795
Net increase (decrease) in cash and cash equivalents												209,993	22
Cash and cash equivalents at beginning of year												22
Cash and cash equivalents at end of year											210,015	210,015	22
Guarantor Subsidiaries
Condensed Consolidating Statements of Cash Flows
Net cash (used in) provided by operating activities												462,855	410,762	373,483
Cash flows from investing activities:
Capital expenditures												(304,190)	(162,517)	(123,005)
Equity investments												(1,880,279)	(252,367)	(171,252)
Acquisition of business, net of cash acquired													(230,728)
Investment in unconsolidated affiliates												(5,227)
Distributions from consolidated affiliates												146,178	68,651	22,246
Proceeds from disposal of property, plant and equipment												1,732	606	733
Net cash flows used in investing activities												(2,041,786)	(576,355)	(271,278)
Cash flows from financing activities:
Proceeds from public equity offerings, net														98
Proceeds (Payments) of intercompany notes, net												12,300	14,990	(12,350)
Contributions from parent and affiliates												55,283	47,295	44,346
Share-based payment activity												907	1,084
Payment of distributions												(75,431)	(50,718)	(41,167)
Payments of SMR Liability												(2,058)	(1,875)	(1,354)
Intercompany advances, net												1,591,329	190,547	(102,376)
Net cash flows provided by financing activities												1,582,330	201,323	(112,803)
Net increase (decrease) in cash and cash equivalents												3,399	35,730	(10,598)
Cash and cash equivalents at beginning of year												99,580	63,850	74,448
Cash and cash equivalents at end of year											102,979	102,979	99,580	63,850
Non-Guarantor Subsidiaries
Condensed Consolidating Statements of Cash Flows
Net cash (used in) provided by operating activities												168,928	137,961	46,852
Cash flows from investing activities:
Restricted cash												(9,497)	2,006	(28,001)
Capital expenditures												(1,627,912)	(399,992)	(347,231)
Acquisition of business, net of cash acquired												(506,797)
Proceeds from disposal of property, plant and equipment												77	7,617	7,527
Net cash flows used in investing activities												(2,144,129)	(390,369)	(367,705)
Cash flows from financing activities:
Proceeds (Payments) of intercompany notes, net												(1,142)	23,000
Contributions from parent and affiliates												1,880,279	252,367	171,252
Contribution from non-controlling interest												265,620	126,392	158,293
Payment of distributions												(152,065)	(135,537)	(28,396)
Net cash flows provided by financing activities												1,992,692	266,222	301,149
Net increase (decrease) in cash and cash equivalents												17,491	13,814	(19,704)
Cash and cash equivalents at beginning of year												17,414	3,600	23,304
Cash and cash equivalents at end of year											34,905	34,905	17,414	3,600
Consolidating Adjustments
Condensed Consolidating Statements of Cash Flows
Net cash (used in) provided by operating activities												19,258	(7,243)	(5,965)
Cash flows from investing activities:
Capital expenditures												(19,187)	12,017	13,492
Equity investments												1,935,562	299,662	215,598
Distributions from consolidated affiliates												(221,609)	(119,369)	(63,413)
Investment in intercompany notes, net												12,300	37,990	(12,350)
Proceeds from disposal of property, plant and equipment												(1,213)	(4,773)	(7,527)
Net cash flows used in investing activities												1,705,853	225,527	145,800
Cash flows from financing activities:
Proceeds (Payments) of intercompany notes, net												(11,158)	(37,990)	12,350
Contributions from parent and affiliates												(1,935,562)	(299,662)	(215,598)
Payment of distributions												221,609	119,368	63,413
Net cash flows provided by financing activities												$ (1,725,111)	$ (218,284)	$ (139,835)