Subsequent Events (Unaudited) - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2017	Dec. 31, 2016	Dec. 06, 2016
7.75% second lien notes due 2023
Subsequent Event [Line Items]
Aggregate principal amount of notes issued			$ 584,732,000
Debt instrument maturity year		2023
2.625% convertible senior notes due 2019
Subsequent Event [Line Items]
Aggregate principal amount of notes issued			616,600,000
Debt instrument maturity year		2019
3.125% convertible senior notes due 2024
Subsequent Event [Line Items]
Aggregate principal amount of notes issued			$ 95,900,000
Debt instrument maturity year		2024
Subsequent event | 7.75% second lien notes due 2023
Subsequent Event [Line Items]
Aggregate principal amount of notes issued	$ 139,200,000
Debt instrument maturity year	2023
Subsequent event | 2.625% convertible senior notes due 2019
Subsequent Event [Line Items]
Aggregate principal amount of notes issued	$ 137,800,000
Debt instrument maturity year	2019
Subsequent event | 3.125% convertible senior notes due 2024
Subsequent Event [Line Items]
Aggregate principal amount of notes issued	$ 60,000,000
Debt instrument maturity year	2024