Earnings Per Common Share - Historical Net Income and Weighted Average Number of Shares of Common Stock Outstanding (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Weighted average number of shares of common stock outstanding	23,742	23,560
Shares assumed issued (less shares assumed purchased for treasury) for stock-based compensation	114	259
Outstanding shares for diluted earnings per share calculation	23,856	23,819