Convertible Notes and Long-term Debt Obligations - Schedule of Aggregate Amount of Interest Expense Recognized (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Disclosure [Abstract]
Contractual interest coupon	$ 32,061	$ 26,019	$ 5,938
Amortization of debt issuance costs	8,102	5,288	1,207
Amortization of debt discount	97,786	79,479	9,143
Total	$ 137,949	$ 110,786	$ 16,288