CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Capital	Retained earnings	Accumulated Other Comprehensive Income/(Loss)	Treasury Stock
Balance at Dec. 31, 2017	$ 413,569	$ 1,822	$ 75,624	$ 420,275	$ (14,704)	$ (69,448)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,583	0	0	46,583	0	0
Other comprehensive income (loss)	(6,384)	0	0	0	(6,384)	0
Treasury Stock, Value, Acquired, Cost Method	(391)					(391)
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	745	2	743	0	0	0
Employee Stock Ownership Plan (ESOP), Cash Contributions to ESOP	1,087	0	407	0	0	680
Cash Dividends	(12,508)	0	0	(12,508)	0	0
Balance at Dec. 31, 2018	442,701	1,824	76,774	456,716	(23,454)	(69,159)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	48,872	0	0	48,872	0	0
Other comprehensive income (loss)	15,953	0	0	0	15,953	0
Treasury Stock, Value, Acquired, Cost Method	(315)	0	0	0	0	(315)
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	801	3	798	0	0	0
Employee Stock Ownership Plan (ESOP), Cash Contributions to ESOP	1,251	0	422	0	0	829
Cash Dividends	(13,533)	0	0	(13,533)	0	0
Balance at Dec. 31, 2019	557,608	2,005	139,694	492,055	(7,501)	(68,645)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	53,844	0	0	53,844	0	0
Other comprehensive income (loss)	17,265	0	0	0	17,265	0
Treasury Stock, Value, Acquired, Cost Method	(9,220)	0	0	0	0	(9,220)
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	820	2	818	0	0	0
Employee Stock Ownership Plan (ESOP), Cash Contributions to ESOP	1,471	0	308	0	0	1,163
Cash Dividends	(14,313)	0	0	(14,313)	0	0
Balance at Dec. 31, 2020	$ 596,992	$ 2,007	$ 140,820	$ 521,103	$ 9,764	$ (76,702)