Borrowings - 2022 Notes - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Dec. 22, 2015	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Schedule Of Debt Instruments [Line Items]
Loss on extinguishment of debt				$ 4,887	$ 14,566
Interest expense		$ 26,762	$ 15,858	28,741	19,148
2022 Notes [Member]
Schedule Of Debt Instruments [Line Items]
Aggregate principal amount	$ 175,000
Net proceeds from the debt issuance	$ 168,500
Interest rate (as a percent)	11.50%
Loss on extinguishment of debt		25,000		25,000
Interest expense		$ 1,500	$ 5,200	6,700	$ 10,400
Prepayment penalty of extinguishment of debt				20,100
Amortization expense recognized for remaining debt discount at settlement				4,900
2022 Notes [Member] | Interest Expense [Member]
Schedule Of Debt Instruments [Line Items]
Loss on extinguishment of debt				$ 25,000