Acquisition - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Feb. 02, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 255,629	$ 289,441		$ 286,532
Annovation [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			$ 1,482
Other current assets			692
IPR&D			65,000
Goodwill			24,530
Total assets			91,704
Accrued expenses			398
Contingent purchase price			18,000
Deferred tax liability			19,023
Total liabilities			37,421
Total cash price paid upon acquisition and fair value of existing equity interest			$ 54,283