Consolidated Statements of Comprehensive Earnings (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
NET EARNINGS	$ 25,696	$ 23,997
OTHER ITEMS OF COMPREHENSIVE EARNINGS:
Change in unrealized gain on investment securities available-for-sale, before income taxes	26,842	13,483
Reclassification adjustment for realized gains on investment securities included in net earnings, before income taxes	(2)	(5)
Total other items of comprehensive earnings	26,840	13,478
Income tax expense related to other items of comprehensive earnings	(9,394)	(4,717)
COMPREHENSIVE EARNINGS	$ 43,142	$ 32,758

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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