Earnings Per Common Share - Historical Net Income and Weighted Average Number of Shares of Common Stock Outstanding (Detail) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Weighted average number of shares of common stock outstanding	23,418	23,359	23,410	24,054
Shares assumed issued (less shares assumed purchased for treasury) for stock-based compensation	216	84	146	146
Outstanding shares for diluted earnings per share calculation	23,634	23,443	23,556	24,200