Debt - Schedule of Debt Maturities (Details) $ in Millions	Sep. 30, 2026 USD ($)
Debt Instrument [Line Items]
Total	$ 18,300
2026	1,475
2027	2,038
2028	7,118
2029	4,265
2030	1,935
After 2030	1,469
Exchangeable Notes Due 2029
Debt Instrument [Line Items]
Total	294
2026	0
2027	0
2028	0
2029	294
2030	0
After 2030	0
Exchangeable Notes Due 2030
Debt Instrument [Line Items]
Total	425
2026	0
2027	0
2028	0
2029	0
2030	425
After 2030	0
Exchangeable First Lien Notes Due 2030
Debt Instrument [Line Items]
Total	380
2026	0
2027	0
2028	0
2029	0
2030	380
After 2030	0
Other Non-Vehicle Debt
Debt Instrument [Line Items]
Total	5,174
2026	203
2027	18
2028	2,691
2029	2,250
2030	0
After 2030	12
Non-vehicle
Debt Instrument [Line Items]
Total	6,273
2026	203
2027	18
2028	2,691
2029	2,544
2030	805
After 2030	12
Vehicle Debt
Debt Instrument [Line Items]
Total	12,027
2026	1,272
2027	2,020
2028	4,427
2029	1,721
2030	1,130
After 2030	$ 1,457

Long-Term Debt, Maturity, after Year Four

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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