Intangible Assets and Goodwill - Summary of Indefinite-lived Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Acquired Indefinite Lived Intangible Assets [Line Items]
Indefinite-lived intangible asset	$ 644,299	$ 101,000
MDV3800 [Member]
Acquired Indefinite Lived Intangible Assets [Line Items]
Indefinite-lived intangible asset	573,299
MDV9300 [Member]
Acquired Indefinite Lived Intangible Assets [Line Items]
Indefinite-lived intangible asset	$ 71,000	$ 101,000