Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Short Term and Long Term Debt [Line Items]
Secured debt	$ 45,271	$ 42,131
Unsecured debt	57,244	54,723
Total secured and unsecured debt	102,515	96,854
Secured debt fair value	44,817	41,467
Unsecured debt fair value	55,338	52,270
Fair value of Secured and Unsecured debt	100,155	93,738
Level 2
Short Term and Long Term Debt [Line Items]
Fair value of Secured and Unsecured debt	98,032	91,545
Level 3
Short Term and Long Term Debt [Line Items]
Fair value of Secured and Unsecured debt	2,123	2,192
Revolving credit facilities
Short Term and Long Term Debt [Line Items]
Secured debt	4,736	3,931
Unsecured debt	1,864	1,473
Secured debt fair value	4,736	3,931
Unsecured debt fair value	1,858	1,448
Securitization notes payable
Short Term and Long Term Debt [Line Items]
Secured debt	40,534	38,200
Secured debt fair value	40,081	37,537
Senior notes
Short Term and Long Term Debt [Line Items]
Unsecured debt	47,442	46,111
Unsecured debt fair value	45,523	43,676
Other unsecured debt
Short Term and Long Term Debt [Line Items]
Unsecured debt	7,938	7,139
Unsecured debt fair value	$ 7,956	$ 7,146