Consolidated Statement of Changes in Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Total
Balance at Dec. 31, 2011	$ 102	$ 164,328	$ (57,518)	$ 29,284	$ 136,196
Balance (in shares) at Dec. 31, 2011	10,190,526
Increase (Decrease) in Stockholders' Equity
Stock based compensation		1,872			1,872
Exercise of warrant	17				17
Common stock issued for stock compensation plans, net of shares withheld and withholding paid for employee taxes	1	(259)			(258)
Common stock issued for stock compensation plans, net of shares withheld and withholding paid for employee taxes (in shares)	101,354
Net income				109,982	109,982
Other comprehensive income (loss), net of tax			29,068		29,068
Balance at Dec. 31, 2012	103	165,941	(28,450)	139,266	276,860
Balance (in shares) at Dec. 31, 2012	10,291,897
Increase (Decrease) in Stockholders' Equity
Stock based compensation		2,736			2,736
Issuance of stock under warrant agreements	1	(1)
Exercise of warrant	117,784				117,784
Common stock issued for stock compensation plans, net of shares withheld and withholding paid for employee taxes	1	(807)			(806)
Common stock issued for stock compensation plans, net of shares withheld and withholding paid for employee taxes (in shares)	86,175
Net income				10,488	10,488
Other comprehensive income (loss), net of tax			23,734		23,734
Balance at Dec. 31, 2013	105	167,869	(4,716)	149,754	313,012
Balance (in shares) at Dec. 31, 2013	10,495,856
Increase (Decrease) in Stockholders' Equity
Stock based compensation		4,174			4,174
Issuance of stock under warrant agreements	1	(1)
Exercise of warrant	73,422				73,422
Common stock issued for stock compensation plans, net of shares withheld and withholding paid for employee taxes	1	(1,521)			(1,520)
Common stock issued for stock compensation plans, net of shares withheld and withholding paid for employee taxes (in shares)	104,014
Net income				8,099	8,099
Other comprehensive income (loss), net of tax			(19,231)		(19,231)
Balance at Dec. 31, 2014	$ 107	$ 170,521	$ (23,947)	$ 157,853	$ 304,534
Balance (in shares) at Dec. 31, 2014	10,673,292