Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 30, 2016
Derivatives, Fair Value [Line Items]
Fixed interest rate						1.48%
Derivatives in Cash Flow Hedging Relationships [Abstract]
Loss related to effective portion of derivatives recognized in accumulated OCI, gross of tax effect	$ 0	$ 14	$ 0	$ 109
Loss related to effective portion of derivatives reclassified from accumulated OCI to interest expense, gross of tax effect	0	(126)	0	(390)
Net unrealized gain (loss) on derivative instruments not designated as hedging instruments [Abstract]
Net unrealized gain (loss)	0	0	0	0
Liabilities [Abstract]
Derivative liabilities, current	166,473		166,473		$ 0
Derivative liabilities, long-term	0		0		48,361
Cash Convertible Notes Hedges [Member] | Selling, General and Administrative Expenses [Member]
Net unrealized gain (loss) on derivative instruments not designated as hedging instruments [Abstract]
Net unrealized gain (loss)	5,597	67,399	118,112	61,237
Cash Convertible Notes Hedges [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Assets [Abstract]
Derivative assets, current	166,473		166,473		0
Derivative assets, long-term	0		0		48,361
Cash Conversion Derivative [Member] | Selling, General and Administrative Expenses [Member]
Net unrealized gain (loss) on derivative instruments not designated as hedging instruments [Abstract]
Net unrealized gain (loss)	(5,597)	$ (67,399)	(118,112)	$ (61,237)
Cash Conversion Derivative [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Liabilities [Abstract]
Derivative liabilities, current	166,473		166,473		0
Derivative liabilities, long-term	$ 0		$ 0		$ 48,361