Schedule of Weighted Average Shares Outstanding (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Weighted average number of shares outstanding - basic	33,198	33,018	32,301
Stock options	162	0	1
Non-vested stock and stock units	381	0	521
Weighted average number of shares outstanding - diluted	33,741	33,018	32,823
Anti-dilutive securities	221	922	106