Securitizations and Variable Interest Entities (Schedule of Variable Interest Entities) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Variable Interest Entity [Line Items]
Carrying value of total assets	$ 197,241	$ 191,826	$ 185,703
Carrying value of total liabilities	183,709	178,967
Assets sold to nonconsolidated VIEs	783	330
Maximum exposure to loss in nonconsolidated VIEs	3,600	3,097
Non-recourse debt	20,141	17,762
Equity securities	759	681
On-balance sheet variable interest entities
Variable Interest Entity [Line Items]
Carrying value of total assets	10,219	9,856
Carrying value of total liabilities	2,716	2,441
Non-recourse debt	2,710	2,436
On-balance sheet variable interest entities | Consumer | Automotive
Variable Interest Entity [Line Items]
Carrying value of total assets	20,272	20,415
Carrying value of total liabilities	2,824	2,553
Assets sold to nonconsolidated VIEs	0	0
Maximum exposure to loss in nonconsolidated VIEs	0	0
Assets held-in-trust	10,100	10,600
On-balance sheet variable interest entities | Consumer | Automotive | Nonrecourse
Variable Interest Entity [Line Items]
Non-recourse debt	108	113
Off-balance sheet variable interest entities
Variable Interest Entity [Line Items]
Carrying value of total assets	22,555	22,614
Carrying value of total liabilities	3,689	3,426
Off-balance sheet variable interest entities | Consumer | Automotive
Variable Interest Entity [Line Items]
Carrying value of total assets	0	0
Carrying value of total liabilities	0	0
Assets sold to nonconsolidated VIEs	653	227
Maximum exposure to loss in nonconsolidated VIEs	653	227
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	130	103
Maximum exposure to loss in nonconsolidated VIEs	130	103
Off-balance sheet variable interest entities | Commercial | Other
Variable Interest Entity [Line Items]
Carrying value of total assets	2,283	2,199
Carrying value of total liabilities	865	873
Assets sold to nonconsolidated VIEs	0	0
Maximum exposure to loss in nonconsolidated VIEs	2,817	2,767
Equity securities	$ 43	$ 38