Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 55,193	$ 28,852	$ 160,067	$ 74,037
OTHER COMPREHENSIVE (LOSS) INCOME
Unrealized holding (losses) gains arising during the period on available-for-sale securities	(10,583)	1,107	(41,612)	9,807
Less: Reclassification adjustment for realized gains included in net income	54	3	53	2,302
Other comprehensive (loss) gain, before tax effect	(10,637)	1,104	(41,665)	7,505
Less: Tax effect of other comprehensive (loss) income	(2,780)	433	(10,889)	2,944
TOTAL OTHER COMPREHENSIVE (LOSS) INCOME	(7,857)	671	(30,776)	4,561
COMPREHENSIVE INCOME	$ 47,336	$ 29,523	$ 129,291	$ 78,598

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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