Loans and Related Allowance for Credit Losses, Nonaccrual Loans (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	$ 8,172		$ 8,256
Total Nonaccrual loans without related allowance for credit losses	2,148		2,313
Recognized interest income	178	$ 200
Total Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	4,952		4,914
Total Nonaccrual loans without related allowance for credit losses	183		266
Recognized interest income	28	36
Total Commercial [Member] | Commercial and industrial loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	743		662
Nonaccrual loans without related allowance for credit losses	58		149
Recognized interest income	14	14
Total Commercial [Member] | Commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	4,115		4,188
Nonaccrual loans without related allowance for credit losses	110		107
Recognized interest income	14	22
Total Commercial [Member] | Lease financing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual lease financing	94		64
Nonaccrual lease financing without related allowance for credit losses	15		10
Recognized interest income	0	0
Total Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	3,220		3,342
Nonaccrual loans without related allowance for credit losses	1,965		2,047
Recognized interest income	150	164
Total Consumer [Member] | Residential mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	3,086		3,192
Nonaccrual loans without related allowance for credit losses	1,965		2,047
Recognized interest income	136	146
Accounts, Notes, Loans and Financing Receivable Textual [Abstract]
Mortgage loans in process of foreclosure, amount	693		837
Total Consumer [Member] | Auto [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	99		115
Nonaccrual loans without related allowance for credit losses	0		0
Recognized interest income	11	15
Total Consumer [Member] | Other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	35		35
Nonaccrual loans without related allowance for credit losses	0		0
Recognized interest income	3	$ 3
Total Consumer [Member] | Government guaranteed mortgage loans upon foreclosure receivable [Member]
Accounts, Notes, Loans and Financing Receivable Textual [Abstract]
Mortgage loans in process of foreclosure, amount	$ 537		$ 660