Allowance for Credit Losses - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses	$ 26,900
Net addition (reduction) to the allowance for credit losses	$ 2,100
Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Accrued interest on other receivables, write-off criteria, period past due	90 days
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Net addition (reduction) to the allowance for credit losses	$ 2,100
Consumer | Card Services
Financing Receivable, Allowance for Credit Loss [Line Items]
Net addition (reduction) to the allowance for credit losses	2,200
Consumer | Home Lending
Financing Receivable, Allowance for Credit Loss [Line Items]
Net addition (reduction) to the allowance for credit losses	(125)
Wholesale
Financing Receivable, Allowance for Credit Loss [Line Items]
Net addition (reduction) to the allowance for credit losses	$ (30)