CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 81,558	$ 34,108
Other comprehensive income (loss)
Change in net unrealized gain (loss) during the period	(23,285)	8,194
Reclassification adjustments for losses included in income	(41)	(1,595)
Reclassification adjustments for foreign currency translation gains		216
Amortization of losses previously held as available-for-sale	90	25
Other comprehensive income (loss)	(23,236)	6,840
Securities available-for-sale:
Change in net unrealized gain (loss) during the period	(6,287)	3,278
Reclassification adjustments for losses included in income	(11)	(638)
Amortization of losses previously held as available-for-sale	24	10
Income tax (benefit) expense related to items of other comprehensive income (loss)	(6,274)	2,650
Other comprehensive income (loss) net of tax and reclassifications into net income	(16,962)	4,190
Comprehensive income	$ 64,596	$ 38,298

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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