Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Parent	Noncontrolling Interest	Comprehensive Income
Beginning balance (shares) at Dec. 31, 2017		42,753,054
Beginning balance (Total) at Dec. 31, 2017	$ 537,125
Beginning balance (NCI) at Dec. 31, 2017							$ 0
Beginning balance (Parent) at Dec. 31, 2017		$ 4	$ 387,145	$ (431)	$ 141,186	$ 537,125		$ 9,221
Net Income (Loss), Total	8,369
Net Income (Loss), Parent	8,369	0	0	0	8,369	8,369		0
Net Income (Loss), NCI	0						0
Other Comprehensive Income (Loss), Parent		$ 0	0	0	0	(8,334)		(8,334)
Other Comprehensive Income (Loss), NCI							0
Other Comprehensive Income (Loss), Total	(8,334)
Stock Issued During Period, Shares, Shares-based Compensation, Gross		(7,117)
Stock Issued During Period, Value, Restricted Stock Award, Gross	486	$ 0	486	0	0	486	0	0
Cash dividends on common stock	(2,565)	$ 0	0	0	(2,565)	(2,565)	0	0
Ending Balance (shares) at Mar. 31, 2018		42,745,937
Ending Balance (Total) at Mar. 31, 2018	$ 535,081
Ending Balance (Parent) at Mar. 31, 2018		$ 4	387,631	(431)	156,327	535,081		(8,451)
Ending balance (NCI) at Mar. 31, 2018							0
Reclassification due to adoption of ASU 2016-01 | Accounting Standards Update 2016-01 [Member]					9,338			(9,338)
Beginning balance (shares) at Dec. 31, 2018	42,984,578	42,984,578
Beginning balance (Total) at Dec. 31, 2018	$ 540,369
Beginning balance (NCI) at Dec. 31, 2018	20,139						20,139
Beginning balance (Parent) at Dec. 31, 2018	520,230	$ 4	389,141	(431)	140,546	520,230		(9,030)
Net Income (Loss), Total	9,578
Net Income (Loss), Parent	9,469	0	0	0	9,469	9,469		0
Net Income (Loss), NCI	109						109
Other Comprehensive Income (Loss), Parent		$ 0	0	0	0	10,560		10,560
Other Comprehensive Income (Loss), NCI							122
Other Comprehensive Income (Loss), Total	10,682
Stock Issued During Period, Shares, Shares-based Compensation, Gross		24,151
Stock Issued During Period, Value, Restricted Stock Award, Gross	901	$ 0	901	0	0	901	0	0
Cash dividends on common stock	$ (2,569)	$ 0	0	0	(2,569)	(2,569)	0	0
Ending Balance (shares) at Mar. 31, 2019	43,008,729	43,008,729
Ending Balance (Total) at Mar. 31, 2019	$ 558,961
Ending Balance (Parent) at Mar. 31, 2019	538,591	$ 4	$ 390,042	$ (431)	$ 147,446	$ 538,591		$ 1,530
Ending balance (NCI) at Mar. 31, 2019	$ 20,370						$ 20,370