Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Contract with customer, liability, revenue recognized	$ 878	$ 839
Revenue, remaining performance obligation, amount	20,900
Capitalized contract cost, amortization	84	57
Capitalized contract cost, impairment loss	$ 0	$ 0
Minimum
Disaggregation of Revenue [Line Items]
Contract term	25 years
Maximum
Disaggregation of Revenue [Line Items]
Contract term	35 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	64.00%
Revenue, remaining performance obligation, expected timing of satisfaction, period	2 years

Contract With Customer, Term

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Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

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