Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Preferred Stock [Member]	Common Stock [Member]	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2018				$ 0	$ 358,598	$ 614,069			$ (90,373)	$ (49,788)
Beginning balance (Accounting Standards Update 2016-01 [Member]) at Dec. 31, 2018
Beginning balance (Accounting Standards Update 2016-13) at Dec. 31, 2018						613,926
Beginning balance (Accounting Standards Update 2016-02 Retrospective) at Dec. 31, 2018						(143)
Beginning balance, shares at Dec. 31, 2018				0	15,698,178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	$ 102,700					102,700
Other Comprehensive Income (Loss), Net of Tax	$ 40,199									40,199
Dividends, Common Stock, Cash						69,482
Stock Issued During Period, Shares, Dividend Reinvestment Plan					171
Stock Issued During Period, Value, Dividend Reinvestment Plan					$ 3
Stock Issued During Period, Shares, Acquisitions	1,037,205				1,037,205
Stock Issued During Period, Value, Acquisitions					$ 98,275
Allocated Share-based Compensation Expense	$ 5,000				$ 4,999
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures					18,983
Stock Granted, Value, Share-based Compensation, Net of Forfeitures					$ 2,480	273			1,926
Treasury Stock, Shares, Acquired					421,253
Treasury Stock, Value, Acquired, Cost Method									(40,535)
Treasury Stock Reissued Shares For Director Grants	13,500				13,500
Treasury shares reissued for director grants						24			1,349
Ending balance, shares at Dec. 31, 2019				0	16,346,442
Ending balance at Dec. 31, 2019				$ 0	$ 459,389	646,847			(127,633)	(9,589)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 4.24
Net Income (Loss) Attributable to Parent	$ 127,923					127,923
Other Comprehensive Income (Loss), Net of Tax	15,160									15,160
Dividends, Common Stock, Cash						70,601
Stock Issued During Period, Shares, Dividend Reinvestment Plan					36
Stock Issued During Period, Value, Dividend Reinvestment Plan					$ 3
Allocated Share-based Compensation Expense	$ 6,000				$ 5,998
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures					30,341
Stock Granted, Value, Share-based Compensation, Net of Forfeitures					$ 4,697	664			3,031
Treasury Stock, Shares, Acquired					76,000
Treasury Stock, Value, Acquired, Cost Method									(7,507)
Treasury Stock Reissued Shares For Director Grants	13,450				13,450
Treasury shares reissued for director grants						69			1,343
Ending balance, shares at Dec. 31, 2020				0	16,314,197
Ending balance at Dec. 31, 2020	$ 1,040,256	$ (7,956)	$ 1,032,300	$ 0	$ 460,687	704,764			(130,766)	5,571
Ending balance (Accounting Standards Update 2016-13) at Dec. 31, 2020							$ (7,956)	$ 696,808
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 4.28
Net Income (Loss) Attributable to Parent	$ 153,945					153,945
Other Comprehensive Income (Loss), Net of Tax	9,584									9,584
Dividends, Common Stock, Cash						74,634
Stock Issued During Period, Shares, Dividend Reinvestment Plan					45
Stock Issued During Period, Value, Dividend Reinvestment Plan					$ 6
Allocated Share-based Compensation Expense	$ 6,300				$ 6,345
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures					29,670
Stock Granted, Value, Share-based Compensation, Net of Forfeitures					$ 5,226	(141)			2,964
Treasury Stock, Shares, Acquired					137,659
Treasury Stock, Value, Acquired, Cost Method									(16,048)
Treasury Stock Reissued Shares For Director Grants	13,400				13,400
Treasury shares reissued for director grants						316			1,360
Ending balance, shares at Dec. 31, 2021				0	16,219,563
Ending balance at Dec. 31, 2021	$ 1,110,759			$ 0	$ 461,800	$ 776,294			$ (142,490)	$ 15,155
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Cash Paid	$ 4.52