Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Partners Capital [Abstract]
Net income	$ 1,929,149	$ 1,918,080	$ 1,408,306
Other comprehensive income (loss), net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	184,906	(86,523)	(19,766)
Cash flow hedges adjustments	108,520	6,091	(9,912)
Foreign currency translation adjustments	1,091	(2,225)	2,241
Defined benefit plans liability adjustments	(81,116)	43,243	22,288
Total other comprehensive income (loss)	213,401	(39,414)	(5,149)
Total comprehensive income	$ 2,142,550	$ 1,878,666	$ 1,403,157