Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	$ 3,554	$ 2,240
Nonperforming Loans	1,528	1,344
Nonperforming Loans Without an Allowance	$ 547	$ 548
Percentage, 90 Days Past Due and Accruing	1.11%	0.72%
Percentage, Nonperforming Loans	0.48%	0.43%
Percentage, Nonperforming Loans Without an Allowance	0.17%	0.18%
Interest income for loans classified as nonperforming	$ 91	$ 66
Credit Card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,499	2,240
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	3,367	2,135
Nonperforming Loans Without an Allowance	0	0
Credit Card: \| International card businesses:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	132	105
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	758	634
Nonperforming Loans Without an Allowance	19	8
Consumer Banking: \| Auto
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	712	595
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	46	39
Nonperforming Loans Without an Allowance	19	8
Commercial Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	55	0
Nonperforming Loans	761	701
Nonperforming Loans Without an Allowance	528	540
Commercial Banking: \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	425	271
Nonperforming Loans Without an Allowance	335	246
Commercial Banking: \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	55	0
Nonperforming Loans	336	430
Nonperforming Loans Without an Allowance	$ 193	$ 294

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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- Definition

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

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- Definition

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

+ References

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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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- Definition

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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