Stockholders' Equity - Additional Information (Detail) - USD ($)		12 Months Ended
	Dec. 14, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Apr. 30, 2012
Class of Stock [Line Items]
Preferred stock, shares issued		0	0
Preferred stock authorized		5,000,000	5,000,000
Authorized stock repurchase value		$ 300,000,000			$ 25,000,000
Common stock repurchased and retired, shares		0
Common stock repurchased and retired, per shares value	$ 4.49	$ 6.70
Common stock repurchased and retired, aggregate value	$ 49,900,000
Preferred stock, shares outstanding		0	0
Open Market Transaction [Member]
Class of Stock [Line Items]
Common stock repurchased and retired, shares			3,400,000	13,900,000
Common stock repurchased and retired, aggregate value			$ 23,000,000	$ 93,100,000
Privately Negotiated Transactions [Member]
Class of Stock [Line Items]
Common stock repurchased and retired, shares	11,100,000