Condensed Consolidated Statements of Shareholders' Equity (unaudited) $ in Thousands	USD ($)
Balance at beginning of period at Dec. 31, 2014	$ 250,371
Balance at beginning of period, as adjusted at Dec. 31, 2014	250,371
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,400
Cash dividends declared	(2,760)
Issuance of common stock	80
Share based compensation	772
Share based compensation withholding obligation	(66)
Repurchase of common stock	(3,668)
Net change in accumulated other comprehensive loss, net of related tax effect	246
Balance at end of period at Jun. 30, 2015	254,375
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,619
Net change in accumulated other comprehensive loss, net of related tax effect	(1,188)
Balance at end of period at Jun. 30, 2015	254,375
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of change in accounting principle	0
Balance at beginning of period at Dec. 31, 2015	251,092
Balance at beginning of period, as adjusted at Dec. 31, 2015	252,339
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	10,538
Cash dividends declared	(3,451)
Issuance of common stock	56
Share based compensation	825
Share based compensation withholding obligation	(627)
Repurchase of common stock	(15,510)
Net change in accumulated other comprehensive loss, net of related tax effect	2,753
Balance at end of period at Jun. 30, 2016	246,923
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	6,438
Net change in accumulated other comprehensive loss, net of related tax effect	1,516
Balance at end of period at Jun. 30, 2016	246,923
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of change in accounting principle	$ 1,247