Treasury Stock - Additional Information (Detail) - USD ($)	3 Months Ended		112 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	May 03, 2017	Dec. 31, 2016	Dec. 31, 2013
Equity, Class of Treasury Stock [Line Items]
Common stock amount authorized under repurchase program, value (up to)				$ 189,800,000.0
Addition to authorized amount				$ 39,800,000.0
Repurchase of common stock (in shares)	895,787	470,000
Payment for repurchase of common stock, net of fees	$ 12,500,000
Average stock price of shares repurchased (in dollars per share)	$ 13.92	$ 9.15
Payments for treasury stock	$ 11,459,000	$ 4,048,000
Accrued value of repurchase of common stock	$ 1,000,000	$ 300,000
Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Remaining authorized repurchase amount			$ 43,400,000
Repurchase of common stock (in shares)			12,834,734
Average stock price of shares repurchased (in dollars per share)			$ 11.41
Payments for treasury stock			$ 146,400,000
Maximum
Equity, Class of Treasury Stock [Line Items]
Common stock amount authorized under repurchase program, value (up to)					$ 150,000,000.0