Equity in Net Assets of Non-consolidated Affiliates (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Total assets	$ 113,786	$ 113,825
Total liabilities	99,992	100,227
Finance charge income	4,103	3,996	$ 4,071
Provision for loan losses	248	881	726
Income before income taxes	5,036	2,702	2,104
Net income	3,789	2,009	1,567
Undistributed earnings of foreign subsidiaries	207	373
Non-consolidated affiliates
Schedule of Equity Method Investments [Line Items]
Finance receivables, net	24,293	22,063
Total assets	26,265	24,722
Debt	18,675	18,236
Total liabilities	22,353	21,177
Finance charge income	1,668	1,447	1,369
Provision for loan losses	32	162	47
Income before income taxes	774	572	630
Net income	582	426	473
Undistributed earnings of foreign subsidiaries	$ 740	$ 647
SAIC-GMAC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	35.00%	35.00%
Dividends declared	$ 309	$ 294	140
Cash dividends received	82	$ 103	$ 49
SAIC-GMAC | Dividends Declared But Not Fully Paid
Schedule of Equity Method Investments [Line Items]
Cash dividends received	$ 108
SAIC-GMF Leasing Co. Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage	35.00%	35.00%