Debt - Convertible Bond Hedge, Warrant Transactions and 2014 Term Loan Facility (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			1 Months Ended	3 Months Ended	12 Months Ended
	Aug. 17, 2015	Feb. 13, 2014	Aug. 31, 2015	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Nov. 30, 2014	Feb. 28, 2014	Feb. 14, 2014	Feb. 11, 2014
Convertible Bond Hedge
Common stock covered under convertible bond hedge (in shares)		7.4
Exercise price (in dollars per unit)		$ 27.09
Purchase of convertible bond hedges, net of tax				$ 39,800
Warrant Transactions
Number of shares of common stock called by warrants								7.4
Exercise price (in dollars per share)								$ 34.12
Exercise price above last reported sale price of common stock (as a percent)								70.00%
Proceeds from issuance of warrants						$ 25,620
Sale price of common stock (in dollars per share)										$ 20.07
Proceeds from Issuance of Warrants						$ 25,620
2014 Term Loan Facility
Loss on debt extinguishment					$ 10,449
Convertible 2.5% notes
Debt
Aggregate principal amount of debt issued									$ 200,000
2014 Term Loan Facility
2014 Term Loan Facility
Repayment of debt			$ 323,000
Loss on debt extinguishment			$ 10,400
Lumara Health | 2014 Term Loan Facility
Debt
Aggregate principal amount of debt issued							$ 340,000
2014 Term Loan Facility
Repayment of debt	$ 323,000
Loss on debt extinguishment					$ 10,400