Significant Accounting Policies - Shares used in Computation of Basic and Diluted Per Share Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Weighted average shares outstanding:
Weighted average number of shares outstanding for basic per share calculation	17,055,619	18,385,783	17,011,306	18,357,362
Effect of dilutive potential shares:
Options	4,032	1,867	3,937	1,781
Nonvested stock	67,366	35,608	73,220	37,310
Adjusted weighted average shares for diluted per share calculation	17,127,017	18,423,258	17,088,463	18,396,453
Anti-dilutive shares	39,756	342,949	180,966	373,288