Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 16,026	$ 11,702
Unrealized gains on available-for-sale securities arising during the period	5,660	4,348
Reclassification adjustment for gains	(4,276)	0
Other comprehensive income before income taxes	1,384	4,348
Tax effect	(511)	(1,605)
Other comprehensive income, net of tax	873	2,743
Comprehensive Income, Net of Tax	$ 16,899	$ 14,445

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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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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

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