Business Acquisition - Summary of Pro Forma Financial Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
MDV3800 [Member]
Business Acquisition [Line Items]
Total revenues	$ 943,258	$ 710,487
Net income (loss)	$ 201,161	230,271
MDV9300 [Member]
Business Acquisition [Line Items]
Total revenues		710,487	$ 272,942
Net income (loss)		$ 274,626	$ (45,685)