Supplemental Condensed Consolidating Financial Information (Schedule of Condensed Consolidating Statement of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net cash (used in) provided by operating activities	$ 309,172	$ 482,927
Cash flows from investing activities:
Acquisitions of facilities and other related equipment	(10,492)	(245,227)
Purchases of property and equipment	(294,991)	(386,461)
Proceeds from sale of property and equipment	2,056	3,437
Increase in other investments	(134,389)	(162,316)
Net cash used in investing activities	(437,816)	(790,567)
Cash flows from financing activities:
Proceeds from exercise of stock options	103,626	1,269
Repurchase of restricted stock shares for payroll tax withholding requirements	(14,569)	(9,074)
Stock buy-back	(27,133)
Deferred financing costs	(924)	(63,986)
Excess tax benefit relating to stock-based compensation	6,331	1,037
Proceeds from noncontrolling investors in joint ventures	64	637
Redemption of noncontrolling investments in joint ventures	(701)	(35,888)
Distributions to noncontrolling investors in joint ventures	(37,937)	(34,590)
Borrowings under credit agreements	296,001	3,633,589
Issuance of long-term debt		1,025,000
Proceeds from receivables facility	300,000	300,000
Repayments of long-term indebtedness	(632,700)	(4,525,110)
Net cash provided by (used in) financing activities	(7,942)	292,884
Net change in cash and cash equivalents	(136,586)	(14,756)
Cash and cash equivalents at beginning of period	387,813	129,865
Cash and cash equivalents at end of period	251,227	115,109
Parent Guarantor [Member]
Cash flows from operating activities:
Net cash (used in) provided by operating activities	(77,788)	(23,273)
Cash flows from financing activities:
Proceeds from exercise of stock options	103,626	1,269
Repurchase of restricted stock shares for payroll tax withholding requirements	(14,569)	(9,074)
Stock buy-back	(27,133)
Excess tax benefit relating to stock-based compensation	6,331	1,037
Changes in intercompany balances with affiliates, net	9,533	30,041
Net cash provided by (used in) financing activities	77,788	23,273
Issuer [Member]
Cash flows from operating activities:
Net cash (used in) provided by operating activities	4,246	(59,325)
Cash flows from financing activities:
Deferred financing costs	(924)	(63,986)
Changes in intercompany balances with affiliates, net	221,906	(16,362)
Borrowings under credit agreements	275,000	3,615,000
Issuance of long-term debt		1,025,000
Repayments of long-term indebtedness	(500,228)	(4,500,327)
Net cash provided by (used in) financing activities	(4,246)	59,325
Other Guarantors [Member]
Cash flows from operating activities:
Net cash (used in) provided by operating activities	425,234	358,137
Cash flows from investing activities:
Acquisitions of facilities and other related equipment	(5,301)	(237,543)
Purchases of property and equipment	(253,801)	(252,067)
Proceeds from sale of property and equipment	1,000	1,460
Increase in other investments	(109,997)	(116,339)
Net cash used in investing activities	(368,099)	(604,489)
Cash flows from financing activities:
Changes in intercompany balances with affiliates, net	(203,171)	239,214
Borrowings under credit agreements	20,441	18,589
Repayments of long-term indebtedness	(13,706)	(11,880)
Net cash provided by (used in) financing activities	(196,436)	245,923
Net change in cash and cash equivalents	(139,301)	(429)
Cash and cash equivalents at beginning of period	271,559	8,920
Cash and cash equivalents at end of period	132,258	8,491
Non-Guarantors [Member]
Cash flows from operating activities:
Net cash (used in) provided by operating activities	(42,520)	207,388
Cash flows from investing activities:
Acquisitions of facilities and other related equipment	(5,191)	(7,684)
Purchases of property and equipment	(41,190)	(134,394)
Proceeds from sale of property and equipment	1,056	1,977
Increase in other investments	(24,392)	(45,977)
Net cash used in investing activities	(69,717)	(186,078)
Cash flows from financing activities:
Proceeds from noncontrolling investors in joint ventures	64	637
Redemption of noncontrolling investments in joint ventures	(701)	(35,888)
Distributions to noncontrolling investors in joint ventures	(37,937)	(34,590)
Changes in intercompany balances with affiliates, net	(28,268)	(252,893)
Borrowings under credit agreements	560
Proceeds from receivables facility	300,000	300,000
Repayments of long-term indebtedness	(118,766)	(12,903)
Net cash provided by (used in) financing activities	114,952	(35,637)
Net change in cash and cash equivalents	2,715	(14,327)
Cash and cash equivalents at beginning of period	116,254	120,945
Cash and cash equivalents at end of period	$ 118,969	$ 106,618