Condensed Consolidating Information - Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities	$ 196,340	$ 164,378	$ 643,211	$ 708,297
Net cash used in investing activities	(167,332)	(71,571)	(226,466)	(125,274)
Net cash provided by (used in) financing activities	(30,185)	(38,418)	(92,288)	(470,596)
Increase (decrease) in cash and equivalents	(1,177)	54,389	324,457	112,427
Cash and equivalents at beginning of period	1,052,666	419,401	727,032	361,363
Cash and equivalents at end of period	1,051,489	473,790	1,051,489	473,790
Parent
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities			280,767	306,941
Net cash used in investing activities			(143,427)	(35,100)
Net cash provided by (used in) financing activities			198,393	(126,984)
Increase (decrease) in cash and equivalents			335,733	144,857
Cash and equivalents at beginning of period			636,877	265,313
Cash and equivalents at end of period	972,610	410,170	972,610	410,170
Guarantors
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities			358,657	400,910
Net cash used in investing activities			(81,983)	(82,737)
Net cash provided by (used in) financing activities			(297,596)	(347,111)
Increase (decrease) in cash and equivalents			(20,922)	(28,938)
Cash and equivalents at beginning of period			81,976	81,690
Cash and equivalents at end of period	61,054	52,752	61,054	52,752
Combined Non-Guarantors
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities			52	(4,302)
Net cash used in investing activities			(3,935)	(12,796)
Net cash provided by (used in) financing activities			13,529	13,606
Increase (decrease) in cash and equivalents			9,646	(3,492)
Cash and equivalents at beginning of period			8,179	14,360
Cash and equivalents at end of period	$ 17,825	$ 10,868	17,825	10,868
Consolidating Adjustments
Condensed Consolidating Statements of Cash Flows
Net cash provided by (used in) operating activities			3,735	4,748
Net cash used in investing activities			2,879	5,359
Net cash provided by (used in) financing activities			$ (6,614)	$ (10,107)