Leasing (Ally as the Lessor) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Residual value guarantee, percentage	15.00%	15.00%
Vehicles	$ 11,496	$ 12,304
Accumulated depreciation	(1,927)	(1,860)
Investment in operating leases, net	$ 9,569	10,444
Minimum
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Lessor, term of contract	24 months
Maximum
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Lessor, term of contract	60 months
Vehicles
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Residual value of leased asset	$ 19	$ 56

Residual Value Guarantee

No definition available.

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- Definition

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of residual asset covered by residual value guarantee under operating lease. Excludes guarantee considered to be lease payments for lessor.

+ References

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- Definition

Amount of accumulated depreciation of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

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- Definition

Amount, before accumulated depreciation, of lessor's underlying asset for which right to use has been conveyed to lessee under operating 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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Amount, after accumulated depreciation, of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

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