Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Distributed earnings allocated to common stock	$ 6,073	$ 5,767	$ 18,220	$ 17,302
Undistributed Earnings, Diluted	5,673	8,081	19,809	17,349
Net Income (Loss) Available to Common Stockholders, Diluted	$ 11,746	$ 13,848	$ 38,029	$ 34,651
Average shares outstanding (in shares)	15,363,000	15,608,000	15,509,000	15,545,000
Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants	62,000	62,000	62,000	60,000
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	20,000	120,000	23,000	108,000
Shares for diluted earnings per share (in shares)	15,445,000	15,790,000	15,594,000	15,713,000
Basic earnings per share (in dollars per share)	$ 0.76	$ 0.89	$ 2.45	$ 2.23
Diluted earnings per share (in dollars per share)	$ 0.76	$ 0.88	$ 2.44	$ 2.21
Options to purchase shares of common stock, anti-dilutive (in shares)	13,953	0
Common stock exercise price, lower limit (in dollars per share)	$ 44.43