CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Common Stock and Paid in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance, beginning of the period (in shares) at Dec. 31, 2021		34,252,632
Balance, beginning of the period at Dec. 31, 2021	$ 1,690,327		$ 1,299,381	$ 390,762	$ 184
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	43,963			43,963
Other Comprehensive Income (Loss), Net of Tax	(154,275)				(154,275)
Accrual of dividends on common stock	(15,066)			(15,066)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		120,152
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	(1,169)		(1,169)
Balance, end of the period (in shares) at Mar. 31, 2022		34,372,784
Balance, end of the period at Mar. 31, 2022	$ 1,563,780		1,298,212	419,659	(154,091)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.44
Balance, beginning of the period (in shares) at Dec. 31, 2021		34,252,632
Balance, beginning of the period at Dec. 31, 2021	$ 1,690,327		1,299,381	390,762	184
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	140,998
Other Comprehensive Income (Loss), Net of Tax	(369,374)
Balance, end of the period (in shares) at Sep. 30, 2022		34,191,759
Balance, end of the period at Sep. 30, 2022	$ 1,408,659		1,291,741	486,108	(369,190)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 1.32
Balance, beginning of the period (in shares) at Mar. 31, 2022		34,372,784
Balance, beginning of the period at Mar. 31, 2022	$ 1,563,780		1,298,212	419,659	(154,091)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	47,965			47,965
Other Comprehensive Income (Loss), Net of Tax	(101,824)				(101,824)
Accrual of dividends on common stock	(15,378)			(15,378)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		18,546
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	2,247		2,247
Repurchase of common stock (in shares)		(200,000)
Repurchase of common stock	(10,960)		(10,960)
Balance, end of the period (in shares) at Jun. 30, 2022		34,191,330
Balance, end of the period at Jun. 30, 2022	$ 1,485,830		1,289,499	452,246	(255,915)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.44
Net Income (Loss) Attributable to Parent	$ 49,070			49,070
Other Comprehensive Income (Loss), Net of Tax	(113,275)				(113,275)
Accrual of dividends on common stock	(15,208)			(15,208)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		429
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	2,242		2,242
Balance, end of the period (in shares) at Sep. 30, 2022		34,191,759
Balance, end of the period at Sep. 30, 2022	$ 1,408,659		1,291,741	486,108	(369,190)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.44
Net Income (Loss) Attributable to Parent	$ 54,380			54,380
Other Comprehensive Income (Loss), Net of Tax	6,421				6,421
Accrual of dividends on common stock	(15,246)			(15,246)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		2,259
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	2,218		2,218
Balance, end of the period (in shares) at Dec. 31, 2022		34,194,018
Balance, end of the period at Dec. 31, 2022	$ 1,456,432		1,293,959	525,242	(362,769)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.44
Net Income (Loss) Attributable to Parent	$ 55,555			55,555
Other Comprehensive Income (Loss), Net of Tax	37,133				37,133
Accrual of dividends on common stock	(16,691)			(16,691)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		114,522
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	(734)		(734)
Balance, end of the period (in shares) at Mar. 31, 2023		34,308,540
Balance, end of the period at Mar. 31, 2023	$ 1,531,695		1,293,225	564,106	(325,636)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.48
Balance, beginning of the period (in shares) at Dec. 31, 2022		34,194,018
Balance, beginning of the period at Dec. 31, 2022	$ 1,456,432		1,293,959	525,242	(362,769)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	141,000
Other Comprehensive Income (Loss), Net of Tax	(30,146)
Balance, end of the period (in shares) at Sep. 30, 2023		34,345,949
Balance, end of the period at Sep. 30, 2023	$ 1,520,607		1,297,307	616,215	(392,915)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 1.44
Balance, beginning of the period (in shares) at Mar. 31, 2023		34,308,540
Balance, beginning of the period at Mar. 31, 2023	$ 1,531,695		1,293,225	564,106	(325,636)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	39,591			39,591
Accrual of dividends on common stock	(16,670)			(16,670)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		36,087
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	1,709		1,709
Balance, end of the period (in shares) at Jun. 30, 2023		34,344,627
Balance, end of the period at Jun. 30, 2023	$ 1,542,513		1,294,934	587,027	(339,448)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.48
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax	$ (13,812)				(13,812)
Net Income (Loss) Attributable to Parent	45,854			45,854
Other Comprehensive Income (Loss), Net of Tax	(53,467)
Accrual of dividends on common stock	(16,666)			(16,666)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		1,322
Amortization of stock-based compensation related to restricted stock grants, net of shares surrendered	2,373		2,373
Balance, end of the period (in shares) at Sep. 30, 2023		34,345,949
Balance, end of the period at Sep. 30, 2023	$ 1,520,607		$ 1,297,307	$ 616,215	(392,915)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.48
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax	$ (53,467)				$ (53,467)