Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	$ 3,502		$ 3,554
Nonperforming Loans	1,783		1,528
Nonperforming Loans Without an Allowance	$ 737		$ 547
Percentage, 90 Days Past Due and Accruing	1.11%		1.11%
Percentage, Nonperforming Loans	0.57%		0.48%
Percentage, Nonperforming Loans Without an Allowance	0.23%		0.17%
Interest income for loans classified as nonperforming	$ 5	$ 2
Credit Card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,479		$ 3,499
Nonperforming Loans	9		9
Nonperforming Loans Without an Allowance	0		0
Credit Card: \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,339		3,367
Nonperforming Loans Without an Allowance	0		0
Credit Card: \| International card businesses:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	140		132
Nonperforming Loans	9		9
Nonperforming Loans Without an Allowance	0		0
Consumer Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	626		758
Nonperforming Loans Without an Allowance	21		19
Consumer Banking: \| Auto
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	585		712
Nonperforming Loans Without an Allowance	0		0
Consumer Banking: \| Retail banking
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	41		46
Nonperforming Loans Without an Allowance	21		19
Commercial Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	23		55
Nonperforming Loans	1,148		761
Nonperforming Loans Without an Allowance	716		528
Commercial Banking: \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	5		0
Nonperforming Loans	541		425
Nonperforming Loans Without an Allowance	369		335
Commercial Banking: \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	18		55
Nonperforming Loans	607		336
Nonperforming Loans Without an Allowance	$ 347		$ 193

Financing Receivable, Nonaccrual, No Allowance, Percent Past Due

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- Definition

Financing Receivable, Percent 90 Days Past Due and Still Accruing

+ References

No definition available.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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Percentage of nonaccrual financing receivable balance outstanding that is past due.

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Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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