Net Income Per Share (Computation of Weighted Average Shares Outstanding Basic and Diluted) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Common shares	22,167,771	23,293,173	22,356,299	23,491,872
Vested restricted stock units	485,622	680,926	765,989	659,208
Basic number of weighted average shares outstanding	22,653,393	23,974,099	23,122,288	24,151,080
Dilutive effect of stock options	0	37,814	6,646	38,536
Dilutive effect of restricted stock and restricted stock units	5,498	5,360	28,355	30,787
Dilutive number of weighted average shares outstanding	22,658,891	24,017,273	23,157,289	24,220,403
Stock Options, Restricted Stock Or Restricted Stock Units [Member]
Shares outstanding excluded from calculation of diluted net income per share	0	0	0	0