Consolidated Statements of Comprehensive Earnings (Loss) - (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
NET EARNINGS	$ 37,633	$ 28,255	$ 72,152	$ 54,854
OTHER ITEMS OF COMPREHENSIVE EARNINGS (LOSS):
Change in unrealized gain (loss) on investment securities available-for-sale, before income taxes	(11,600)	17,725	(54,306)	26,953
Reclassification adjustment for realized gains on investment securities included in net earnings, before income tax	(67)	(747)	(1,288)	(750)
Total other items of comprehensive earnings (loss)	(11,667)	16,978	(55,594)	26,203
Income tax benefit (expense) related to other items of comprehensive earnings	2,450	(5,842)	11,675	(9,171)
Reclassification of certain income tax effects related to the change in the U.S. statutory federal income tax rate under the Tax Cuts and Jobs Act to retained earnings			5,759
COMPREHENSIVE EARNINGS	$ 28,416	$ 39,391	$ 33,992	$ 71,886

Tax Cuts and Jobs Act of 2017, reclassification from AOCI to retained earnings.

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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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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