Finance Receivables and Loans, Net (Finance Receivables and Loans Redefaulted During the Period) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) loan	Jun. 30, 2022 USD ($) loan
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,218	4,331
Amortized cost	$ 35	$ 68
Charge-off amount	$ 14	$ 27
Consumer \| Automotive
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	2,138	4,249
Amortized cost	$ 35	$ 66
Charge-off amount	$ 14	$ 27
Consumer \| Consumer mortgage
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	3
Amortized cost	$ 0	$ 2
Charge-off amount	$ 0	$ 0
Consumer \| Mortgage Finance
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	1	3
Amortized cost	$ 0	$ 2
Charge-off amount	$ 0	$ 0
Consumer \| Other
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	79	79
Amortized cost	$ 0	$ 0
Charge-off amount	$ 0	$ 0
Consumer \| Credit Card
Accounts, Notes, Loans and Financing Receivable
Number of loans \| loan	79	79
Amortized cost	$ 0	$ 0
Charge-off amount	$ 0	$ 0

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