Derivatives and Hedging Activities (Details Textual) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Derivative [Line Items]
Margin on interest rate swaps	$ 137		$ 137		$ 8
Carrying values of hedged liabilities	9,200		9,200		7,800
Cumulative amount of fair value hedging adjustment	(250)		(250)		(236)
Net increase (decrease) in interest expense on long term debt and other	47	$ 3	130	$ (88)
Fair Value Hedging | Fixed-Rate Debt Obligations
Derivative [Line Items]
Fixed-rate debt obligations designated in fair value hedging relationships	9,500		9,500		8,100
Net Investment Hedges
Derivative [Line Items]
Notional amount of derivatives	13,100		13,100		12,500
Gains (losses) on net investment hedges, net of taxes	244	520	(261)	728
Reclassifications out of AOCI	0	0	0	0
Foreign Exchange Contract | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount of derivatives	22,300		22,300		21,700
Foreign Exchange Contract | Not Designated as Hedging Instrument | Other Expense
Derivative [Line Items]
Gains in changes in fair value of derivatives not designated as hedges	26	23	56	10
Equity Linked Embedded Derivative | Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount of derivatives	78		78		$ 78
Equity Linked Embedded Derivative | Not Designated as Hedging Instrument | Noninterest Income
Derivative [Line Items]
Losses on embedded derivative	$ 12	$ 0	$ 12	$ 4