Treasury Stock - Additional Information (Detail) - USD ($)	12 Months Ended			111 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Mar. 27, 2017	Dec. 31, 2013
Equity Class Of Treasury Stock [Line Items]
Common stock amount authorized under repurchase program, value	$ 189,800,000.0
Addition to authorized amount	$ 39,800,000.0
Repurchase of common stock (in shares)	5,598,094	96,277
Payment for repurchase of common stock, net of fees	$ 73,700,000
Average stock price of shares repurchased (in dollars per share)	$ 13.17	$ 17.66
Payments for treasury stock	$ 74,265,000	$ 1,702,000	$ 12,809,000
Maximum
Equity Class Of Treasury Stock [Line Items]
Common stock amount authorized under repurchase program, value					$ 150,000,000.0
Subsequent Event
Equity Class Of Treasury Stock [Line Items]
Remaining authorized repurchase amount				$ 49,800,000
Repurchase of common stock (in shares)				12,376,835
Average stock price of shares repurchased (in dollars per share)				$ 11.31
Payments for treasury stock				$ 140,000,000