Borrowings - 2022 Notes - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended
	Dec. 22, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Schedule Of Debt Instruments [Line Items]
Debt maturity date				Jul. 15, 2020
Interest expense		$ 21,149,000	$ 4,482,000	$ 29,729,000	$ 9,048,000
2022 Notes [Member]
Schedule Of Debt Instruments [Line Items]
Aggregate principal amount	$ 175,000,000
Net proceeds from the debt issuance	$ 168,500,000
Interest rate (as a percent)	11.50%
Semi-annual installments of principal	$ 21,875,000
Debt maturity date	Dec. 15, 2022
Interest expense		$ 5,200,000		$ 10,400,000