Significant Accounting Policies - Shares used in Computation of Basic and Diluted Per Share Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Weighted average shares outstanding:
Weighted average number of shares outstanding for basic per share calculation	17,083,201	17,656,842	17,035,541	18,121,217
Effect of dilutive potential shares:
Options	4,208	1,935	4,032	1,849
Nonvested stock	94,604	68,042	70,102	37,423
Adjusted weighted average shares for diluted per share calculation	17,182,013	17,726,819	17,109,675	18,160,489
Anti-dilutive shares	94,299	176,641	181,648	348,595