Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - 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]
Unrealized gain (loss) on interest rate swaps, tax	$ 0	$ 0	$ (4)	$ 1
Reclassification adjustment for losses recognized in earnings, tax	(9)	(25)	(31)	(77)
Unrealized gains (losses) on other-than-temporarily impaired securities available for sale arising during the period, tax	0	0	0	(47)
Reclassification adjustment for realized gains included in net income, tax	0	0	0	484
Unrealized (losses) gains on other securities available for sale arising during the period, tax	653	433	2,010	(1,111)
Reclassification adjustment for available for sale realized gains included in net income, tax	$ 0	$ 2	$ 0	$ 56

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale category and out of the held-to-maturity category.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax (expense) benefit of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

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Amount of tax (expense) benefit of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss, attributable to the parent entity.

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