Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2021	$ 723,209	$ 0	$ 0	$ 352,122	$ 363,742	$ 7,345
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	72,243				72,243
Other comprehensive (loss) income, net of tax	(130,466)					(130,466)
Amortization of unearned compensation	1,770			1,770
Exercise of stock options	108			108
Stock option expense	13			13
Net settlement of share awards	(1,785)			(1,785)
Stock retirement plans	609			609
Cash dividends on common stock	(20,708)				(20,708)
Ending balance at Sep. 30, 2022	644,993	0	0	352,837	415,277	(123,121)
Beginning balance at Jun. 30, 2022	657,865	0	0	352,412	398,517	(93,064)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	23,821				23,821
Other comprehensive (loss) income, net of tax	(30,057)					(30,057)
Amortization of unearned compensation	627			627
Exercise of stock options	14			14
Net settlement of share awards	(89)			(89)
Stock retirement plans	(127)			(127)
Cash dividends on common stock	(7,061)				(7,061)
Ending balance at Sep. 30, 2022	644,993	0	0	352,837	415,277	(123,121)
Beginning balance at Dec. 31, 2022	677,375	0	0	354,188	429,385	(106,198)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	53,196				53,196
Other comprehensive (loss) income, net of tax	(17,236)					(17,236)
Amortization of unearned compensation	2,647			2,647
Net settlement of share awards	(1,204)			(1,204)
Stock retirement plans	(153)			(153)
Cash dividends on common stock	(21,256)				(21,256)
Ending balance at Sep. 30, 2023	693,369	0	0	355,478	461,325	(123,434)
Beginning balance at Jun. 30, 2023	709,243	0	0	354,953	452,209	(97,919)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	16,205				16,205
Other comprehensive (loss) income, net of tax	(25,515)					(25,515)
Amortization of unearned compensation	944			944
Net settlement of share awards	(482)			(482)
Stock retirement plans	63			63
Cash dividends on common stock	(7,089)				(7,089)
Ending balance at Sep. 30, 2023	$ 693,369	$ 0	$ 0	$ 355,478	$ 461,325	$ (123,434)