Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total	Cumulative Change, Adjusted Balance [Member] Common Stock [Member]	Cumulative Change, Adjusted Balance [Member] Retained Earnings [Member]	Cumulative Change, Adjusted Balance [Member] Accumulated Other Comprehensive Income (Loss) [Member]	Cumulative Change, Adjusted Balance [Member]	Cumulative Change, Adjustment [Member] Common Stock [Member]	Cumulative Change, Adjustment [Member] Retained Earnings [Member]	Cumulative Change, Adjustment [Member] Accumulated Other Comprehensive Income (Loss) [Member]	Cumulative Change, Adjustment [Member]
Balance at beginning of period at Dec. 31, 2019	$ 352,344	$ 1,611	$ (3,786)	$ 350,169
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	19,582	0	19,582
Cash dividends declared	0	(8,855)	0	(8,855)
Repurchase of common stock	(13,784)	0	0	(13,784)
Issuance of common stock	11	0	0	11
Share based compensation	1,009	0	0	1,009
Share based compensation withholding obligation	(591)	0	0	(591)
Other comprehensive income	0	0	7,582	7,582
Balances at end of period at Jun. 30, 2020	338,989	12,338	3,796	355,123
Balance at beginning of period at Mar. 31, 2020	338,528	1,944	(4,854)	335,618
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	14,772	0	14,772
Cash dividends declared	0	(4,378)	0	(4,378)
Issuance of common stock	0	0	0	0
Share based compensation	462	0	0	462
Share based compensation withholding obligation	(1)	0	0	(1)
Other comprehensive income	0	0	8,650	8,650
Balances at end of period at Jun. 30, 2020	338,989	12,338	3,796	355,123
Balance at beginning of period at Dec. 31, 2020	339,353	40,145	10,024	389,522	$ 339,353	$ 29,842	$ 10,024	$ 379,219
Balance at beginning of period (ASU 2016-13 [Member]) at Dec. 31, 2020									$ 0	$ (10,303)	$ 0	$ (10,303)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	34,425	0	34,425
Cash dividends declared	0	(9,166)	0	(9,166)
Repurchase of common stock	(7,285)	0	0	(7,285)
Issuance of common stock	49	0	0	49
Share based compensation	947	0	0	947
Share based compensation withholding obligation	(607)	0	0	(607)
Other comprehensive income	0	0	(1,608)	(1,608)
Balances at end of period at Jun. 30, 2021	332,457	55,101	8,416	395,974
Balance at beginning of period at Mar. 31, 2021	335,704	47,287	4,338	387,329
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	12,388	0	12,388
Cash dividends declared	0	(4,574)	0	(4,574)
Repurchase of common stock	(3,684)	0	0	(3,684)
Issuance of common stock	30	0	0	30
Share based compensation	505	0	0	505
Share based compensation withholding obligation	(98)	0	0	(98)
Other comprehensive income	0	0	4,078	4,078
Balances at end of period at Jun. 30, 2021	$ 332,457	$ 55,101	$ 8,416	$ 395,974