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v3.23.2

Fair Value Measurements Fair Value Measurements (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Sep. 30, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |
Financing Receivable, after Allowance for Credit Loss |  | $ 127 |  | $ 127 |  | $ 96 |
Investments |  |  |  |  |  |  |
Government debt securities |  | 363 |  | 363 |  | 394 |
Corporate debt securities |  | 444 |  | 444 |  | 283 |
Mortgage and asset-backed securities |  | 35 |  | 35 |  | 52 |
Institutional mutual funds |  | 290 |  | 290 |  | 242 |
Forward debt securities contracts |  | 8 |  | 8 |  | 4 |
Private credit measured at net asset value |  | 144 |  | 144 |  | 103 |
Private equity funds measured at net asset value(1) |  | 605 |  | 605 |  | 487 | [1]
Private real estate funds measured at net asset value(1) |  | 382 |  | 382 |  | 369 | [1]
Commingled funds measured at net asset value(1) |  | 1,273 |  | 1,273 |  | 1,203 | [1]
Total investments |  | 4,202 |  | 4,202 |  | 3,671 |
Commodity contract derivatives |  | 22 |  | 22 |  | 152 |
Total derivatives not subject to master netting or similar arrangement |  | 22 |  | 22 |  | 152 |
Total |  | 4,224 |  | 4,224 |  | 3,946 |
Liabilities |  |  |  |  |  |  |
Currency swaps | [2] | 161 |  | 161 |  | 240 |
Interest rate swaps |  | 837 |  | 837 |  | 905 |
Commodity contract derivatives |  | 11 |  | 11 |  | 7 |
Derivative Liability, Not Subject to Master Netting Arrangement |  | 11 |  | 11 |  | 7 |
Total |  | 1,256 |  | 1,256 |  | 1,160 |
Decommissioning Fund Investments |  | 1,200 |  | 1,200 |  |  |
Balance in NDT |  | 2,900 |  | 2,900 |  |  |
Equity Securities, FV-NI |  | 658 |  | 658 |  | 534 |
Commodity Contract under FHP |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Total derivatives not subject to master netting or similar arrangement |  |  |  |  |  | 123 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Not Subject to Master Netting Arrangement |  | 247 |  | 247 |  | 8 |
NDT [Member] |  |  |  |  |  |  |
Liabilities |  |  |  |  |  |  |
Debt and Equity Securities, Unrealized Gain (Loss) |  | 31 | $ 105 | 79 | $ 85 |  |
Debt and Equity Securities, Unrealized Gain (Loss) |  | 31 | 105 | 79 | 85 |  |
ART [Member] |  |  |  |  |  |  |
Liabilities |  |  |  |  |  |  |
Debt and Equity Securities, Unrealized Gain (Loss) |  | 7 | 35 | 23 | 26 |  |
Debt and Equity Securities, Unrealized Gain (Loss) |  | 7 | $ 35 | 23 | $ 26 |  |
Fair Value, Inputs, Level 1 |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Government debt securities |  | 302 |  | 302 |  | 358 |
Corporate debt securities |  | 0 |  | 0 |  | 0 |
Mortgage and asset-backed securities |  | 0 |  | 0 |  | 0 |
Institutional mutual funds |  | 290 |  | 290 |  | 242 |
Forward debt securities contracts |  | 0 |  | 0 |  | 0 |
Private credit measured at net asset value |  | 0 |  | 0 |  | 0 |
Private equity funds measured at net asset value(1) | [1] |  |  |  |  | 0 |
Private real estate funds measured at net asset value(1) |  | 0 |  | 0 |  | 0 | [1]
Commingled funds measured at net asset value(1) |  | 0 |  | 0 |  | 0 | [1]
Total investments |  | 1,250 |  | 1,250 |  | 1,134 |
Commodity contract derivatives |  | 0 |  | 0 |  | 0 |
Total |  | 1,250 |  | 1,250 |  | 1,134 |
Liabilities |  |  |  |  |  |  |
Currency swaps |  | 0 |  | 0 |  | 0 | [2]
Interest rate swaps |  | 0 |  | 0 |  | 0 |
Commodity contract derivatives |  | 0 |  | 0 |  | 0 |
Total |  | 0 |  | 0 |  | 0 |
Equity Securities, FV-NI |  | 658 |  | 658 |  | 534 |
Fair Value, Inputs, Level 1 | Commodity Contract under FHP |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Total derivatives not subject to master netting or similar arrangement |  |  |  |  |  | 0 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Not Subject to Master Netting Arrangement |  | 0 |  | 0 |  | 0 |
Fair Value, Inputs, Level 2 |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Government debt securities |  | 61 |  | 61 |  | 36 |
Corporate debt securities |  | 444 |  | 444 |  | 283 |
Mortgage and asset-backed securities |  | 35 |  | 35 |  | 52 |
Institutional mutual funds |  | 0 |  | 0 |  | 0 |
Forward debt securities contracts |  | 8 |  | 8 |  | 4 |
Private credit measured at net asset value |  | 0 |  | 0 |  | 0 |
Private equity funds measured at net asset value(1) | [1] |  |  |  |  | 0 |
Private real estate funds measured at net asset value(1) |  | 0 |  | 0 |  | 0 | [1]
Commingled funds measured at net asset value(1) |  | 0 |  | 0 |  | 0 | [1]
Total investments |  | 548 |  | 548 |  | 375 |
Commodity contract derivatives |  | 22 |  | 22 |  | 152 |
Total |  | 570 |  | 570 |  | 650 |
Liabilities |  |  |  |  |  |  |
Currency swaps |  | 161 |  | 161 |  | 240 | [2]
Interest rate swaps |  | 837 |  | 837 |  | 905 |
Commodity contract derivatives |  | 11 |  | 11 |  | 7 |
Total |  | 1,256 |  | 1,256 |  | 1,160 |
Equity Securities, FV-NI |  | 0 |  | 0 |  | 0 |
Fair Value, Inputs, Level 2 | Commodity Contract under FHP |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Total derivatives not subject to master netting or similar arrangement |  |  |  |  |  | 123 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Not Subject to Master Netting Arrangement |  | 247 |  | 247 |  | 8 |
Fair Value, Inputs, Level 3 |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Government debt securities |  | 0 |  | 0 |  | 0 |
Corporate debt securities |  | 0 |  | 0 |  | 0 |
Mortgage and asset-backed securities |  | 0 |  | 0 |  | 0 |
Institutional mutual funds |  | 0 |  | 0 |  | 0 |
Forward debt securities contracts |  | 0 |  | 0 |  | 0 |
Private credit measured at net asset value |  | 0 |  | 0 |  | 0 |
Private equity funds measured at net asset value(1) | [1] |  |  |  |  | 0 |
Private real estate funds measured at net asset value(1) |  | 0 |  | 0 |  | 0 | [1]
Commingled funds measured at net asset value(1) |  | 0 |  | 0 |  | 0 | [1]
Total investments |  | 0 |  | 0 |  | 0 |
Commodity contract derivatives |  | 0 |  | 0 |  | 0 |
Total |  | 0 |  | 0 |  | 0 |
Liabilities |  |  |  |  |  |  |
Currency swaps |  | 0 |  | 0 |  | 0 | [2]
Interest rate swaps |  | 0 |  | 0 |  | 0 |
Commodity contract derivatives |  | 0 |  | 0 |  | 0 |
Total |  | 0 |  | 0 |  | 0 |
Equity Securities, FV-NI |  | 0 |  | 0 |  | 0 |
Fair Value, Inputs, Level 3 | Commodity Contract under FHP |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |
Total derivatives not subject to master netting or similar arrangement |  |  |  |  |  | 0 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Not Subject to Master Netting Arrangement |  | $ 0 |  | $ 0 |  | $ 0 |
[1] | Certain investments that are measured at fair value using the NAV per share (or its equivalent) practical expedient have not been categorized in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented on the Consolidated Balance Sheets.(4) TVA records currency swaps net of cash collateral received from or paid to the counterparty if applicable, to the extent such amount is not recorded in Accounts payable and accrued liabilities. See Note 13 — Risk Management Activities and Derivative Transactions — Offsetting of Derivative Assets and Liabilities.
[2] | TVA records currency swaps net of cash collateral received from or paid to the counterparty if applicable, to the extent such amount is not recorded in Accounts payable and accrued liabilities. See Note 13 — Risk Management Activities and Derivative Transactions — Offsetting of Derivative Assets and Liabilities.

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- Definition The fair value measurements of private partnerships measured at net asset value. Private partnership investments may include holdings of investments in private real estate, venture capital, buyout, mezzanine or subordinated debt, restructuring or distressed debt, and special situations through funds management by third-party managers. + References No definition available. + Details
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- Definition Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(12)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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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 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-3 + Details
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- Definition The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481961/940-320-45-2 + Details
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