Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
NET EARNINGS	$ 56,379	$ 53,470	$ 113,297	$ 90,701
OTHER ITEMS OF COMPREHENSIVE EARNINGS:
Change in unrealized gain on investment securities available-for-sale, before income taxes	24,659	36,524	(42,111)	109,561
Reclassification adjustment for realized gains on investment securities included in net earnings, before income taxes	(5)	(1,512)	(813)	(3,574)
Total other items of comprehensive earnings	24,654	35,012	(42,924)	105,987
Income tax benefit (expense) related to:
Change in unrealized gain on investment securities available-for-sale	(5,178)	(7,670)	8,843	(23,008)
Reclassification adjustment for realized gains on investment securities included in net earnings	1	318	172	751
Total income tax benefit (expense)	(5,177)	(7,352)	9,015	(22,257)
COMPREHENSIVE EARNINGS	$ 75,856	$ 81,130	$ 79,388	$ 174,431

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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