Inventories, Net Inventories, Net (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Inventories, Net
Materials and supplies inventory	$ 808	$ 775
Fuel inventory	303	198
Renewable energy certificates/emissions allowance inventory, net	18	12
Allowance for inventory obsolescence	(57)	(35)
Inventories, net	1,072	$ 950
Increase (Decrease) in Coal Inventories	58
Increase (Decrease) in Fuel Inventories	105
Increase (Decrease) in Other Fossil Fuel Inventories	$ 32

Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process.

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- Definition

The increase (decrease) during the reporting period in the value of coal held in inventory.

+ References

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The increase (decrease) during the reporting period in the value of fuel held in inventory.

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- Definition

The increase (decrease) during the reporting period in the value of fossil fuel, other than coal, held in inventory.

+ References

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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- Definition

Amount of valuation reserve for inventory.

+ References

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Amount, after of valuation reserves and allowances, of inventory, classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

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- Definition

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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No definition available.

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