Net Income Per Common Share (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net Income Per Common Share
Weighted average common basic shares outstanding	15,668,129	15,704,837	15,632,817	15,776,883
Effect of dilutive stock options and restricted stock units (in shares)	260,556	329,493	250,718	339,253
Weighted average common diluted shares outstanding	15,928,685	16,034,330	15,883,535	16,116,136
Net income per share:
Basic (in dollars per share)	$ 0.15	$ 0.38	$ 0.56	$ 0.91
Diluted (in dollars per share)	$ 0.15	$ 0.37	$ 0.55	$ 0.89
Anti dilutive securities excluded in computation of diluted earnings per share
Anti-dilutive options (in shares)		9,534		9,534