Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income		$ 103,858	$ 66,536	$ 279,906	$ 184,859
Other comprehensive income/(loss), net of tax:
Changes in unrealized gains/(losses) on available-for-sale securities	[1],[2],[3]	(3,138)	4,736	(28,065)	12,283
Amortization of losses of securities transferred to held-to-maturity from available-for-sale	[1],[2]		439		1,348
Changes in unrealized gains/(losses) on cash flow hedging instruments	[1],[2],[4]	(1,523)	183	1,895	698
Foreign currency translation adjustment	[1],[2]	(1,336)	2,644	(3,434)	7,178
Total other comprehensive income/(loss), net of tax	[1],[2]	(5,997)	8,002	(29,604)	21,507
Comprehensive income		$ 97,861	$ 74,538	$ 250,302	$ 206,366

[1] Net of tax benefit of $2.1 million and tax expense of $5.0 million for the three months ended September 30, 2018 and 2017, respectively. Net of tax benefit of $10.4 million and tax expense of $13.5 million for the nine months ended September 30, 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 risk. The reclassification is reflected in the activity for the nine months ended September 30, 2018. See Note 2 for further details.

[3] There were no reclassifications to earnings during the three and nine months ended September 30, 2018 and 2017, respectively.

[4] Amounts are net of reclassifications to earnings of gains of $1.5 million and $0.7 million for the three months ended September 30, 2018 and 2017, respectively. Amounts are net of reclassifications to earnings of gains of $3.3 million and losses of $0.8 million for the nine months ended September 30, 2018 and 2017, respectively.