Summary of Significant Accounting Policies (Details 1)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation between basic and diluted earnings per share
Weighted average common shares outstanding for the year	31,708,949	31,178,813	30,764,282
Dilutive impact of stock equivalents	436,824	368,778	269,432
Weighted average common and common equivalent shares for the year	32,145,773	31,547,591	31,033,714
Common shares outstanding at December 31	31,728,969	31,032,791	30,773,908
Weighted average anti-dilutive shares excluded from the computation of diluted earnings per share	189,768	470,097	938,546