Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Series A 3% Preferred Stock [Member]	Series B-1 8.48% Preferred Stock [Member]	Preferred Equity [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Series A 3% Preferred Stock [Member]	Retained Earnings [Member] Series B-1 8.48% Preferred Stock [Member]	Accumulated Other Comprehensive income [Member]	Treasury Stock [Member]
Balance at Dec. 31, 2020	$ 468,363			$ 17,328	$ 161	$ 125,118	$ 324,850			$ 2,128	$ (1,222)
Comprehensive income:
Net income	20,710						20,710
Other comprehensive loss, net of tax	(12,700)									(12,700)
Common stock issued	301					3					298
Purchases of common stock for treasury	(5,963)										(5,963)
Purchases of 8.48% preferred stock	(6)			(6)
Share-based compensation plans:
Share-based compensation	216					216
Restricted stock units released						(446)					446
Cash dividends declared:
Preferred stock dividends per share		$ (1)	$ (364)					$ (1)	$ (364)
Common stock dividends per share	(4,272)						(4,272)
Balance at Mar. 31, 2021	466,284			17,322	161	124,891	340,923			(10,572)	(6,441)
Balance at Dec. 31, 2020	468,363			17,328	161	125,118	324,850			2,128	(1,222)
Comprehensive income:
Net income	40,910
Other comprehensive loss, net of tax	(8,062)									(8,062)
Balance at Jun. 30, 2021	487,126			17,292	161	125,253	356,485			(5,934)	(6,131)
Balance at Mar. 31, 2021	466,284			17,322	161	124,891	340,923			(10,572)	(6,441)
Comprehensive income:
Net income	20,200						20,200
Other comprehensive loss, net of tax	4,638									4,638
Purchases of common stock for treasury	(1)										(1)
Purchases of 8.48% preferred stock	(37)			(30)		(7)
Share-based compensation plans:
Share-based compensation	562					562
Restricted stock awards issued						(223)					223
Stock awards	118					30					88
Cash dividends declared:
Preferred stock dividends per share		(1)	(365)					(1)	(365)
Common stock dividends per share	(4,272)						(4,272)
Balance at Jun. 30, 2021	487,126			17,292	161	125,253	356,485			(5,934)	(6,131)
Balance at Dec. 31, 2021	505,142			17,292	161	126,105	384,007			(13,207)	(9,216)
Comprehensive income:
Net income	14,983						14,983
Other comprehensive loss, net of tax	(53,887)									(53,887)
Purchases of common stock for treasury	(15,026)										(15,026)
Share-based compensation plans:
Share-based compensation	443					443
Restricted stock units released						(667)					667
Cash dividends declared:
Preferred stock dividends per share		(1)	(364)					(1)	(364)
Common stock dividends per share	(4,444)						(4,444)
Balance at Mar. 31, 2022	446,846			17,292	161	125,881	394,181			(67,094)	(23,575)
Balance at Dec. 31, 2021	505,142			17,292	161	126,105	384,007			(13,207)	(9,216)
Comprehensive income:
Net income	30,631
Other comprehensive loss, net of tax	(86,518)									(86,518)
Balance at Jun. 30, 2022	425,801			17,292	161	125,568	405,019			(99,725)	(22,514)
Balance at Mar. 31, 2022	446,846			17,292	161	125,881	394,181			(67,094)	(23,575)
Comprehensive income:
Net income	15,648						15,648
Other comprehensive loss, net of tax	(32,631)									(32,631)
Purchases of common stock for treasury	(301)										(301)
Share-based compensation plans:
Share-based compensation	947					947
Restricted stock units released						(917)					917
Restricted stock awards issued						(332)					332
Stock awards	102					(11)					113
Cash dividends declared:
Preferred stock dividends per share		$ (1)	$ (363)					$ (1)	$ (363)
Common stock dividends per share	(4,446)						(4,446)
Balance at Jun. 30, 2022	$ 425,801			$ 17,292	$ 161	$ 125,568	$ 405,019			$ (99,725)	$ (22,514)