Debt - Interest Expense and LT Debt Maturities (Details) $ in Millions	Jun. 30, 2020 USD ($)
Debt Instrument [Line Items]
2020 (July 1, 2020 to December 31, 2020)	$ 23,182
2021	29,415
2022	20,038
2023	22,339
2024	6,245
2025	8,805
Thereafter	17,194
Total	127,218
Automotive [Member]
Debt Instrument [Line Items]
2020 (July 1, 2020 to December 31, 2020)	1,489
2021	1,908
2022	5,160
2023	13,010
2024	75
2025	2,540
Thereafter	11,253
Total	35,435
GM Financial [Member]
Debt Instrument [Line Items]
2020 (July 1, 2020 to December 31, 2020)	21,693
2021	27,507
2022	14,878
2023	9,329
2024	6,170
2025	6,265
Thereafter	5,941
Total	$ 91,783

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal in Year One

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- Definition

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal, Remainder of Fiscal Year

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No definition available.

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- Definition

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal after Year Six

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No definition available.

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- Definition

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal in Year Five

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No definition available.

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- Definition

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal in Year Four

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No definition available.

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- Definition

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal in Year Three

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No definition available.

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- Definition

Long-term Debt and Finance Lease Obligations, Maturities, Repayments of Principal in Year Two

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No definition available.

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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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No definition available.

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- Definition

Amount of long-term debt and lease obligation, including portion classified as current.

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No definition available.

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