Earnings Per Share Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								9 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]
Net income as reported	$ 3,621	$ 8,410	$ 11,033	$ 10,040	$ 5,415	$ 7,930	$ 8,766	$ 6,185	$ 28,296	$ 33,104	$ 28,296	$ 25,423
Preferred stock dividend									(1,488)	0		(1,750)
Accretion of preferred stock discount									(1,707)	0		(774)
Net income available to common shareholders	3,621	8,410	11,033	10,040	4,153	7,282	8,122	5,544	25,101	33,104	25,101	22,899
Impact of assumed conversions
Interest on 9% convertible trust preferred securities, net of income tax									1,485	1,015		1,485
Net income available to common shareholders and assumed conversions									$ 26,586	$ 34,119		$ 24,384
Weighted average common shares outstanding (in shares)									17,859,000	18,582,000		16,683,000
Incremental shares from assumed conversions of convertible trust preferred securities (in shares)									1,439,000	1,001,000		1,439,000
Additional dilutive common stock equivalents (in shares)									40,000	168,000		23,000
Diluted common shares outstanding (in shares)									19,338,000	19,751,000		18,145,000
Basic earnings per common share: (in dollars per share)	$ 0.19	$ 0.45	$ 0.61	$ 0.56	$ 0.23	$ 0.41	$ 0.46	$ 0.31	$ 1.41	$ 1.78	$ 1.41	$ 1.37
Diluted earnings per common share: (in dollars per share)	$ 0.18	$ 0.44	$ 0.58	$ 0.53	$ 0.23	$ 0.39	$ 0.44	$ 0.31	$ 1.37	$ 1.73	$ 1.37	$ 1.34
Antidilutive Securities Excluded from Computation of Earnings Per Share
Common stock equivalents excluded from earnings per share calculations due to anti-dilutive effect (in shares)									1,027,683	517,694		899,493
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Convertible trust preferred securities, interest rate, stated percentage	10.00%									10.00%
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share
Common stock equivalents excluded from earnings per share calculations due to anti-dilutive effect (in shares)									324,074			324,074
Convertible Debt Securities
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Convertible trust preferred securities, interest rate, stated percentage	9.00%				9.00%					9.00%	9.00%