Debt - Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Long-term debt
Other	$ 297	$ 6,508
Long-term Debt	3,604,681	3,679,720
Less: current portion	297	6,508
Less: deferred financing costs	26,049	18,012
Long-term debt	3,578,335	3,655,200
Maturity of primary debt
2018	828,759
2019	303,489
2020	833,175
2021	696,000
Thereafter	947,300
Total	$ 3,608,723
2.35% senior notes due September 2016
Long-term debt
Senior Notes		347,955
Interest rate on senior notes due (as a percent)	2.35%
6.15% senior notes due February 2018
Long-term debt
Senior Notes	$ 827,539	921,162
Interest rate on senior notes due (as a percent)	6.15%
9.25% senior notes due January 2019
Long-term debt
Senior Notes	$ 303,489	339,607
Interest rate on senior notes due (as a percent)	9.25%
5.00% senior notes due September 2020
Long-term debt
Senior Notes	$ 669,540	683,839
Interest rate on senior notes due (as a percent)	5.00%
4.625% senior notes due September 2021
Long-term debt
Senior Notes	$ 694,868	698,628
Interest rate on senior notes due (as a percent)	4.625%
5.10% senior notes due September 2023
Long-term debt
Senior Notes	$ 346,448	349,021
Interest rate on senior notes due (as a percent)	5.10%
5.50% senior notes due January 2023
Long-term debt
Senior Notes	$ 600,000
Interest rate on senior notes due (as a percent)	5.50%
Term Loan Facility
Long-term debt
Senior Notes	$ 162,500	325,000
Revolving Credit Facility
Long-term debt
Revolving credit facility	0
Commercial paper
Long-term debt
Revolving credit facility	$ 0
Long-term Debt		$ 8,000