GM Financial Receivables and Transactions - Allowance for Loan Losses (Details) - GM Financial - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses at beginning of period	$ 1,886	$ 1,978
Provision for loan losses	122	(26)
Charge-offs	(275)	(253)
Recoveries	177	150
Effect of foreign currency	18	(14)
Allowance for loan losses at end of period	$ 1,928	$ 1,835

Amount of foreign currency translation gain (loss) which (increases) decreases allowance for credit loss on financing receivable.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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