Risk Management Activities and Derivative Transactions Counterparty Credit Risk (Details) $ in Millions |
9 Months Ended | ||
|---|---|---|---|
|
Jun. 30, 2025
USD ($)
Customers
|
Jun. 30, 2024 |
Sep. 30, 2024
USD ($)
|
|
| Derivative | |||
| Accounts Receivable, before Allowance for Credit Loss, Current | $ | $ 1,791 | $ 1,683 | |
| Two Largest Customer Percentage of Total Operating Revenue | 1600.00% | 1600.00% | |
| Moody's, A1 Rating [Member] | |||
| Derivative | |||
| Natural Gas Banking Counterparties Credit Rating | A1 | ||
| Moody's, B1 Rating [Member] | |||
| Derivative | |||
| Natural Gas Banking Counterparties Credit Rating | B1 | ||
| Moody's, A2 Rating | |||
| Derivative | |||
| Banking Counterparties Credit Rating | A2 | ||
| Credit of Customers | |||
| Derivative | |||
| Number of customers that represent the percent of sales | 2 | ||
| Number of customers that represent the percent of sales | 2 | ||