Residual Value Guarantee

No definition available.

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Namespace Prefix:	ally_
Data Type:	dtr-types1:percentItemType
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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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+ Details

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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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-URI https://asc.fasb.org/1943274/2147479773/842-30-50-3

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Balance Type:	debit
Period Type:	instant

- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 840
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Balance Type:	debit
Period Type:	instant

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- Details

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- Details

Name:	ally_ResidualValueOfLeasedAssetAxis=ally_A15OfManufacturerSuggestedRetailPriceMember
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Balance Type:
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- Details

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Leasing - Schedule of Ally as the Lessor (Details) - USD ($) $ in Millions	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Vehicles	$ 9,519				$ 11,015
Accumulated depreciation	(1,528)				(1,930)
Investment in operating leases, net	$ 7,991	$ 7,967	$ 8,126	$ 8,582	9,085	$ 9,509	$ 9,890	$ 10,218
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	$ 1,900				12
Vehicles \| 15% Of Manufacturer Suggested Retail Price
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Residual value of leased asset	$ 1				$ 12
Residual value guarantee, percentage	15.00%				15.00%
Vehicles \| 50% Of Contract Residual Value
Property, Plant, and Equipment, Lessor Asset under Operating Lease [Line Items]
Residual value of leased asset	$ 1,900
Residual value guarantee, percentage	50.00%