Condensed Consolidated Statements of Shareholders' Equity (unaudited) $ in Thousands	USD ($)
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	1,247
Balance at beginning of period at Dec. 31, 2016	248,980
Balance at beginning of period, as adjusted at Dec. 31, 2016	249,332
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,905
Cash dividends declared	(4,266)
Issuance of common stock	57
Share based compensation	916
Share based compensation withholding obligation	(487)
Repurchase of common stock	0
Net change in accumulated other comprehensive loss, net of related tax effect	4,996
Balance at end of period at Jun. 30, 2017	262,453
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,931
Net change in accumulated other comprehensive loss, net of related tax effect	2,724
Balance at end of period at Jun. 30, 2017	262,453
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of change in accounting	$ 352