Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net earnings		$ 131,616	$ 139,996	$ 374,104	$ 470,914
Other comprehensive income (loss), net of tax:
Unrealized net holding gains (losses) on securities available-for-sale arising during the period		(288,174)	(63,956)	(970,572)	(101,403)
Income tax (expense) benefit related to unrealized holding gains (losses) arising during the period		79,132	17,672	266,518	28,185
Unrealized net holding gains (losses) on securities available-for-sale, net of tax		(209,042)	(46,284)	(704,054)	(73,218)
Reclassification adjustment for net (gains) losses included in net earnings	[1]	(86)	(515)	1,019	(616)
Income tax expense (benefit) related to reclassification adjustment		24	142	(279)	170
Reclassification adjustment for net (gains) losses included in net earnings, net of tax		(62)	(373)	740	(446)
Amortization of Unrealized Net Loss on Securities Transferred From Available-For-Sale to Held-to-Maturity, net of tax		0	0	(218,326)	0
OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI for Amortization of Gain (Loss), before Tax1		(7,775)	0	(10,282)	0
Debt Securities, Held-to-maturity, Transfer, Unrealized Gain (Loss)		(2,135)	0	(2,824)	0
Amortization of Unrealized Net Loss on Securities Transferred From Available-For-Sale to Held-to-Maturity, net of tax		5,640	0	7,458	0
Other comprehensive income (loss), net of tax		(203,464)	(46,657)	(914,182)	(73,664)
Comprehensive income (loss)		$ (71,848)	$ 93,339	$ (540,078)	$ 397,250

[1] Entire amounts are recognized in "Gain (loss) on sale of securities" on the Condensed Consolidated Statements of Earnings.