Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement Of Partners Capital [Abstract]
Net income	$ 1,353,152	$ 1,929,149	$ 1,918,080
Other comprehensive income (loss), net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	107,222	184,906	(86,523)
Cash flow hedges adjustments	172,787	108,520	6,091
Foreign currency translation adjustments	2,284	1,091	(2,225)
Defined benefit plans liability adjustments	(138,645)	(81,116)	43,243
Total other comprehensive income (loss)	143,648	213,401	(39,414)
Total comprehensive income	$ 1,496,800	$ 2,142,550	$ 1,878,666