Consolidated Statements Of Comprehensive Income (Parenthetical) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other comprehensive income/(loss), tax	$ 6,000	$ 3,700	$ 8,300	$ 8,500
Reclassifications to earnings of realized gains on available-for-sale securities	0	0	0	0
Reclassifications to earnings of gains/(losses) on cash flow hedging instruments	$ 1,200	$ (600)	1,800	$ (1,500)
ASU 2018-02 [Member]
Reclassification to retained earnings related to cash flow hedges and investment portfolio credit risk			$ 3,000

Amount after tax 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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