Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Short Term and Long Term Debt [Line Items]
Secured debt, carrying amount	$ 49,394	$ 49,573
Unsecured debt, carrying amount	66,994	64,691
Total secured and unsecured debt, carrying amount	116,389	114,264
Secured debt fair value	49,733	49,753
Unsecured debt fair value	68,212	65,258
Fair value of Secured and Unsecured debt	117,945	115,010
Level 2
Short Term and Long Term Debt [Line Items]
Fair value of Secured and Unsecured debt	115,371	112,941
Level 3
Short Term and Long Term Debt [Line Items]
Fair value of Secured and Unsecured debt	2,575	2,070
Revolving credit facilities
Short Term and Long Term Debt [Line Items]
Secured debt, carrying amount	2,127	5,426
Unsecured debt, carrying amount	2,351	2,178
Secured debt fair value	2,127	5,426
Unsecured debt fair value	2,368	2,174
Securitization notes payable
Short Term and Long Term Debt [Line Items]
Secured debt, carrying amount	47,267	44,147
Secured debt fair value	47,606	44,327
Senior notes
Short Term and Long Term Debt [Line Items]
Unsecured debt, carrying amount	55,648	53,632
Unsecured debt fair value	56,810	54,177
Other unsecured debt
Short Term and Long Term Debt [Line Items]
Unsecured debt, carrying amount	8,995	8,880
Unsecured debt fair value	$ 9,035	$ 8,906