Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Partners Capital [Abstract]
Net income	$ 372,136	$ 480,081	$ 882,012	$ 1,436,083
Other comprehensive income (loss), net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	(17,948)	22,605	114,451	177,049
Cash flow hedges adjustments	(63,199)	8,695	240,562	155,666
Foreign currency translation adjustments	2,733	(1,704)	(261)	(2,104)
Defined benefit plans liability adjustments	9,287	3,054	27,431	9,162
Total other comprehensive income (loss)	(69,127)	32,650	382,183	339,773
Total comprehensive income	$ 303,009	$ 512,731	$ 1,264,195	$ 1,775,856