Securitizations and Variable Interest Entities (Schedule of Variable Interest Entities) (Details) - USD ($) $ in Millions	1 Months Ended
	Nov. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Carrying value of total assets		$ 196,392	$ 191,826	$ 182,114
Carrying value of total liabilities		182,626	178,967
Assets sold to nonconsolidated VIEs		2,639	330
Maximum exposure to loss in nonconsolidated VIEs		5,458	3,097
Non-recourse debt		17,570	17,762
Variable interest entity, deconsolidation of assets	$ 1,700
Variable interest entity, deconsolidation of liabilities	1,400
Proceeds from sale of variable interest entity	$ 247
Held-to-maturity securities		4,680	1,062
Other assets		9,395	9,138
Equity securities		810	681
On-balance sheet variable interest entities
Variable Interest Entity [Line Items]
Carrying value of total assets		7,075	9,856
Carrying value of total liabilities		1,513	2,441
Non-recourse debt		1,509	2,436
Other assets		461	645
On-balance sheet variable interest entities | Consumer | Automotive
Variable Interest Entity [Line Items]
Carrying value of total assets		16,415	20,415
Carrying value of total liabilities		1,614	2,553
Assets sold to nonconsolidated VIEs		0	0
Maximum exposure to loss in nonconsolidated VIEs		0	0
Assets held-in-trust		9,300	10,600
On-balance sheet variable interest entities | Consumer | Automotive | Nonrecourse
Variable Interest Entity [Line Items]
Non-recourse debt		100	113
Off-balance sheet variable interest entities
Variable Interest Entity [Line Items]
Carrying value of total assets		19,012	22,614
Carrying value of total liabilities		2,588	3,426
Off-balance sheet variable interest entities | Consumer | Automotive
Variable Interest Entity [Line Items]
Carrying value of total assets		81	0
Carrying value of total liabilities		0	0
Assets sold to nonconsolidated VIEs		2,514	227
Maximum exposure to loss in nonconsolidated VIEs		2,595	227
Held-to-maturity securities		78
Other assets		3
Off-balance sheet variable interest entities | Consumer | Other
Variable Interest Entity [Line Items]
Carrying value of total assets		0	0
Carrying value of total liabilities		0	0
Assets sold to nonconsolidated VIEs		125	103
Maximum exposure to loss in nonconsolidated VIEs		125	103
Off-balance sheet variable interest entities | Commercial | Other
Variable Interest Entity [Line Items]
Carrying value of total assets		2,516	2,199
Carrying value of total liabilities		974	873
Assets sold to nonconsolidated VIEs		0	0
Maximum exposure to loss in nonconsolidated VIEs		2,738	2,767
Equity securities		$ 44	$ 38