Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income		$ 66,536	$ 17,814	$ 184,859	$ 54,640
Other comprehensive income/(loss), net of tax:
Changes in unrealized gains on available-for-sale securities	[1],[2]	4,736	4,494	12,283	14,915
Amortization of losses of securities transferred to held-to-maturity from available-for-sale	[1]	439	1,633	1,348	2,942
Changes in unrealized gains/(losses) on cash flow hedging instruments	[1],[3]	183	4,279	698	(4,128)
Foreign currency translation adjustment	[1]	2,644	(1,036)	7,178	(8,315)
Total other comprehensive income, net of tax	[1]	8,002	9,370	21,507	5,414
Comprehensive income		$ 74,538	$ 27,184	$ 206,366	$ 60,054

[1] Net of tax expense of $5.0 million and $5.8 million for the three months ended September 30, 2017 and 2016, respectively. Net of tax expense of $13.5 million and tax expense of $3.4 million for the nine months ended September 30, 2017 and 2016, respectively.

[2] There were no reclassifications to earnings during the three and nine months ended September 30, 2017 and 2016, respectively.

[3] Amounts are net of reclassifications to earnings of gains of $0.7 million and losses of $1.4 million for the three months ended September 30, 2017 and 2016, respectively. Amounts are net of reclassifications to earnings of losses of $0.8 million and $4.3 million for the nine months ended September 30, 2017 and 2016, respectively.