Consolidated Statements of Changes in Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common stock	Accumulated deficit	Accumulated other comprehensive income (loss)
Balance at Dec. 31, 2011	$ 132,881	$ 329,056	$ (198,884)	$ 2,709
Balance (In shares) at Dec. 31, 2011		47,236,725
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	6,926		5,951	975
Issuance of common stock, net (In shares)		44,917
Issuance of common stock, net	0	0
Restricted stock grants, net (In shares)		44,664
Stock-based compensation expense	1,050	1,050
Tax effect on nonvested restricted stock	(82)	(82)
Balance at Dec. 31, 2012	140,775	330,024	(192,933)	3,684
Balance (In shares) at Dec. 31, 2012		47,326,306
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	47,125		50,845	(3,720)
Issuance of common stock, net (In shares)		68,871
Issuance of common stock, net	30	30
Restricted stock grants, net (In shares)		196,884
Stock-based compensation expense	889	889
Tax effect on nonvested restricted stock	(104)	(104)
Balance at Dec. 31, 2013	188,715	330,839	(142,088)	(36)
Balance (In shares) at Dec. 31, 2013		47,592,061
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	6,608		3,737	2,871
Issuance of common stock, net (In shares)		24,454,170
Issuance of common stock, net	119,285	119,285
Restricted stock grants, net (In shares)		445,619
Stock-based compensation expense	1,214	1,214
Tax effect on nonvested restricted stock	(339)	(339)
Balance at Dec. 31, 2014	$ 315,483	$ 450,999	$ (138,351)	$ 2,835
Balance (In shares) at Dec. 31, 2014		72,491,850