Inventory - Schedule of Inventory (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Coal	$ 104	$ 152
Oil products	69	75
Fuel inventory for electric generation	173	227
Materials and supplies, net	83	72
Environmental products	41	76
Inventory, net	$ 297	$ 375

Inventory, Environmental Products, Net Of Reserves

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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-Name Accounting Standards Codification
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- Definition

Carrying amount as of the balance sheet date of coal, which is a combustible rock or minerals which are extracted from the ground and used as fuel.

+ References

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- Definition

Carrying amount as of the balance sheet date of petroleum or crude oil.

+ References

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- References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Publisher FASB
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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date for elements of machinery or equipment held for the purpose of replacing similar parts in the course of repair or maintenance.

+ References

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