Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income		$ 88,761	$ 65,512
Other comprehensive income/(loss), net of tax:
Changes in unrealized gains/(losses) on available-for-sale securities	[1],[2],[3]	(13,071)	3,777
Amortization of losses of securities transferred to held-to-maturity from available-for-sale	[1],[2]		524
Changes in unrealized gains on cash flow hedging instruments	[1],[2],[4]	2,706	1,033
Foreign currency translation adjustment	[1],[2]	3,736	2,294
Total other comprehensive income/(loss), net of tax	[1],[2]	(6,629)	7,628
Comprehensive income		$ 82,132	$ 73,140

[1] Net of tax benefit of $2.3 million and tax expense of $4.8 million for the three months ended March 31, 2018 and 2017, respectively.

[2] The adoption of ASU 2018-02 on January 1, 2018 resulted in a reclassification of $3.0 million to retained earnings related to cash flow hedges and investment portfolio credit risk. See Note 2 for further details.

[3] There were no reclassifications to earnings during the three months ended March 31, 2018 and 2017, respectively.

[4] Amounts are net of reclassifications to earnings of gains of $0.5 million and losses of $0.9 million for the three months ended March 31, 2018 and 2017, respectively.