Consolidated Statements of Comprehensive Income (Unaudited) - 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	$ 20,692	$ 13,932	$ 59,283	$ 44,646
Unrealized (losses) gains on available-for-sale securities arising during the period	(5,638)	488	(19,520)	9,404
Reclassification adjustment for gains	0	0	0	(4,276)
Other comprehensive (loss) income before income taxes	(5,638)	488	(19,520)	5,128
Tax effect	1,313	(180)	4,544	(1,893)
Other comprehensive (loss) income, net of tax	(4,325)	308	(14,976)	3,235
Comprehensive Income, Net of Tax	$ 16,367	$ 14,240	$ 44,307	$ 47,881

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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