Earnings Per Share (Calculation of Basic and Diluted EPS) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Net income	$ 7,238	$ 6,950
Average Common Shares:
Basic (weighted-average outstanding shares)	12,084	12,006
Dilutive potential common shares from stock options, shares	186	152
Diluted (weighted-average outstanding shares)	12,270	12,158
Basic earnings per share (in dollars per share)	$ 0.60	$ 0.58
Diluted earnings per share (in dollars per share)	$ 0.59	$ 0.57