Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock Outstanding [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Treasury Stock, Common [Member]	Total
Balance (in shares) at Dec. 31, 2021	75,750,862
Beginning balance, loss, net of tax at Dec. 31, 2021	$ 909	$ 972,474	$ (3,065)	$ 1,985,168	$ (509,235)	$ 2,446,251
Dividend Reinvestment Plan (in shares)	21,415
Dividend Reinvestment Plan	$ 0	945	0	0	0	945
Restricted stock units vested (in shares)	10,908
Restricted stock units vested	$ 0	0	0	0	0	0
Shares withheld related to net share settlement of RSUs	$ 0	(285)	0	0	0	(285)
Purchases of treasury stock (in shares)	(704,927)
Purchases of treasury stock	$ 0	0	0	0	(32,896)	(32,896)
Stock-based compensation	0	1,614	0	0	0	1,614
Cash dividends	0	0	0	(25,515)	0	(25,515)
Other comprehensive income	0	0	(42,912)	0	0	(42,912)
Net income	$ 0	0	0	75,028	0	75,028
Balance (in shares) at Mar. 31, 2022	75,078,258
Ending balance, loss, net of tax at Mar. 31, 2022	$ 909	974,748	(45,977)	2,034,681	(542,131)	2,422,230
Balance (in shares) at Dec. 31, 2022	72,742,151
Beginning balance, loss, net of tax at Dec. 31, 2022	$ 911	981,119	(102,295)	2,244,856	(650,551)	2,474,040
Dividend Reinvestment Plan (in shares)	23,020
Dividend Reinvestment Plan	$ 0	918	0	0	0	918
Restricted stock units vested (in shares)	613
Restricted stock units vested	$ 0	0	0	0	0	0
Shares withheld related to net share settlement of RSUs	$ 0	(14)	0	0	0	(14)
Purchases of treasury stock (in shares)	(375,090)
Purchases of treasury stock	$ 0	0	0	0	(16,736)	(16,736)
Stock-based compensation	0	1,511	0	0	0	1,511
Cash dividends	0	0	0	(24,605)	0	(24,605)
Other comprehensive income	0	0	11,218	0	0	11,218
Net income	$ 0	0	0	96,007	0	96,007
Balance (in shares) at Mar. 31, 2023	72,390,694
Ending balance, loss, net of tax at Mar. 31, 2023	$ 911	$ 983,534	$ (91,077)	$ 2,316,258	$ (667,287)	$ 2,542,339