Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Earnings per share, basic and diluted
Net income	$ 3,445	$ 4,594	$ 13,006	$ 11,224
Basic weighted average common shares	18,150,062	18,392,207	18,145,404	18,312,843
Basic earnings per common share	$ 0.19	$ 0.25	$ 0.72	$ 0.61
Stock options	413,958	446,975	403,363	455,461
Restricted stock	8,038	7,284	6,154	6,072
Diluted weighted average common shares	18,572,058	18,846,466	18,554,921	18,774,376
Diluted earnings per common share	$ 0.19	$ 0.24	$ 0.70	$ 0.60
Basic EPS [Member]
Earnings per share, basic and diluted
Net income	3,445	4,594	13,006	11,224
Basic weighted average common shares	18,150,062	18,392,207	18,145,404	18,312,843
Basic earnings per common share	$ 0.19	$ 0.25	$ 0.72	$ 0.61
Diluted EPS [Member]
Earnings per share, basic and diluted
Net income	$ 3,445	$ 4,594	$ 13,006	$ 11,224