Fair Value Measurements - Fair Values and Related Carrying Values of Financial Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, net, carrying amount	$ 1,114	$ 940
Notes receivable, net, fair value	1,117	953
Debt, excluding capital lease obligations, carrying amount	(53,177)	(53,625)
Debt, excluding capital lease obligations, fair value	(53,286)	(51,089)
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, net, fair value	1,109	941
Debt, excluding capital lease obligations, fair value	(53,286)	(51,089)
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, net, fair value	$ 8	$ 12