Net Completed Plant Net Completed Plant (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Completed Plant
Accumulated depreciation	$ 38,793	$ 35,871
Net completed plant	32,196	32,328
Property, Plant and Equipment, Gross	70,989	68,199
Coal-fired
Completed Plant
Completed plant cost	20,177	18,525
Accumulated depreciation	16,635	14,464
Net completed plant	3,542	4,061
Gas and oil-fired
Completed Plant
Completed plant cost	7,051	6,663
Accumulated depreciation	2,112	2,057
Net completed plant	4,939	4,606
Nuclear
Completed Plant
Completed plant cost	26,800	26,803
Accumulated depreciation	14,149	13,557
Net completed plant	12,651	13,246
Transmission
Completed Plant
Completed plant cost	9,964	9,375
Accumulated depreciation	3,450	3,359
Net completed plant	6,514	6,016
Hydroelectric
Completed Plant
Completed plant cost	4,307	4,109
Accumulated depreciation	1,288	1,241
Net completed plant	3,019	2,868
Other electrical plant
Completed Plant
Completed plant cost	1,763	1,798
Accumulated depreciation	737	780
Net completed plant	1,026	1,018
Multipurpose dams
Completed Plant
Completed plant cost	900	900
Accumulated depreciation	413	404
Net completed plant	487	496
Other stewardship
Completed Plant
Completed plant cost	27	26
Accumulated depreciation	9	9
Net completed plant	$ 18	$ 17

Completed Plant

No definition available.

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- Definition

Period end amount of property, plant and equipment (PPE) related to utility distribution less the cumulative amount of depreciation, depletion and amortization related to PPE that has been recognized in the Income Statement.

+ References

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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