Consolidated Statements of Changes in Stockholder's Equity (Unaudited) - USD ($) $ in Thousands	Total	Effect of adopting ASU No. 2016-13 ("CECL")	Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Additional Paid-in-Capital	Additional Paid-in-Capital Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings	Retained Earnings Effect of adopting ASU No. 2016-13 ("CECL")	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Other Comprehensive (Loss)	Accumulated Other Comprehensive (Loss) Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock	Treasury Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock Held by the Employee Stock Ownership Plan	Common Stock Held by the Employee Stock Ownership Plan Cumulative Effect, Period of Adoption, Adjusted Balance	Stock Held by Rabbi Trust	Stock Held by Rabbi Trust Cumulative Effect, Period of Adoption, Adjusted Balance	Deferred Compensation Obligations	Deferred Compensation Obligations Cumulative Effect, Period of Adoption, Adjusted Balance
Balance at beginning of period at Dec. 31, 2020	$ 1,011,287			$ 1,220		$ 609,531		$ 673,084			$ (69,625)		$ (163,015)		$ (39,293)		$ (1,875)		$ 1,260
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	21,045							21,045
Other comprehensive income (loss)	(2,882)										(2,882)
Treasury stock allocated to restricted stock award grants	0					(733)							733
Stock based compensation	2,143					2,143
Purchase of treasury stock	(32,837)												(32,837)
Restricted stock forfeitures	0					242							(242)
Employee Stock Ownership Plan shares committed to be released	925					366									559
Funding of deferred compensation obligations	(32)																(266)		234
Balance at end of year at Mar. 31, 2021	999,649			1,220		611,549		694,129			(72,507)		(195,361)		(38,734)		(2,141)		1,494
Balance at beginning of period at Dec. 31, 2021	1,079,081	$ 6,212	$ 1,085,293	1,246	$ 1,246	667,906	$ 667,906	765,133	$ 6,212	$ 771,345	(45,919)	$ (45,919)	(271,647)	$ (271,647)	(37,026)	$ (37,026)	(2,425)	$ (2,425)	1,813	$ 1,813
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	20,404							20,404
Other comprehensive income (loss)	(54,436)										(54,436)
Issuance of common stock allocated to restricted stock award grants	0			1		(1)
Stock based compensation	1,915					1,915
Purchase of treasury stock	(21,685)												(21,685)
Exercise of stock options	(182)					(182)
Restricted stock forfeitures	0					676							(676)
Repurchase shares for taxes	(113)												(113)
Employee Stock Ownership Plan shares committed to be released	1,206					641									565
Funding of deferred compensation obligations	85																(321)		406
Balance at end of year at Mar. 31, 2022	$ 1,032,487			$ 1,247		$ 670,955		$ 791,749			$ (100,355)		$ (294,121)		$ (36,461)		$ (2,746)		$ 2,219