Earnings per share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings per share

Schedule of reconciliation of weighted average shares used in calculation of basic earnings per share and diluted earnings per share

	Year Ended December 31,
	2011	2010	2009
Weighted average common shares-basic	18,219,343	17,601,956	17,119,474
Effect of diluted securities:
Unexercised stock options net of treasury share repurchase	—	311,589	83,469
Weighted average common share-diluted	18,219,343	17,913,545	17,202,943