Shareholders' Equity - Adjustments to Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Gains (losses) from sales of available-for-sale securities, net	$ (2)	$ 57	$ 4
Net interest income	2,544	1,905	2,200
Compensation and employee benefits expenses	4,428	4,554	4,450
Net income	2,774	2,693	2,420
Net realized gains from sales of available-for-sale securities, taxes	1	(15)	0
Amortization of net unrealized gain (loss), before adjustment, tax	96
Net realized gains from sales of available-for-sale securities, tax	(13)	(25)	(20)
Other comprehensive (income) loss, actuarial losses, tax	(1)	16	3
Reclassification out of Accumulated Other Comprehensive Income
Class of Stock [Line Items]
Net income	122	(65)	(43)
Reclassification out of Accumulated Other Comprehensive Income | Net Unrealized Gains (Losses) on Investment Securities(1)
Class of Stock [Line Items]
Gains (losses) from sales of available-for-sale securities, net	1	(42)	0
Reclassification out of Accumulated Other Comprehensive Income | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Transferred To Held-To-Maturity, Parent
Class of Stock [Line Items]
Net interest income	169		0
Reclassification out of Accumulated Other Comprehensive Income | Net Unrealized Gains (Losses) on Cash Flow Hedges
Class of Stock [Line Items]
Net interest income	(36)	(70)	(52)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of Actuarial Losses
Class of Stock [Line Items]
Compensation and employee benefits expenses	$ (12)	$ 47	$ 9