XML 109 R82.htm IDEA: XBRL DOCUMENT
v3.21.1

Revenue Customer Type (Details) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2021 USD ($) Units | Mar. 31, 2020 USD ($) | Mar. 31, 2021 USD ($) Units | Mar. 31, 2020 USD ($) | Sep. 30, 2021 USD ($)
Revenue, Major Customer [Line Items] |  |  |  |  |
NES's % of operating revenues |  |  | 800.00% |  |
Sales of Electricity | $ 2,533 | $ 2,489 | $ 4,803 | $ 5,021 |
Electric revenue | 2,531 | 2,488 | 4,799 | 5,019 |
Off System Sales of Electricity | 2 |  | 4 | 2 |
Other revenue | 39 | 32 | 73 | 78 |
Revenues | 2,572 | 2,521 | 4,876 | 5,099 |
Bill credits for LTA | $ 48 | 36 | $ 90 | 70 |
Number of LPCs signed LTA | Units | 142 |  | 142 |  |
Number of LPCs signed Flexibility Agreement | Units | 71 |  | 71 |  |
Percent of sales of electricity to LPCs |  |  | 92.00% |  |
Pandemic Relief Credit | $ (55) |  | $ (104) |  | $ 200
lpcs [Domain] |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 2,337 | 2,301 | 4,428 | 4,658 |
industries directly served [Domain] |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 168 | 160 | 322 | 310 |
federal agencies and other [Domain] |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 28 | 28 | 53 | 53 |
ALABAMA |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 379 | 360 | 713 | 729 |
GEORGIA |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 66 | 64 | 124 | 127 |
KENTUCKY |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 157 | 158 | 294 | 315 |
MISSISSIPPI |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 237 | 227 | 449 | 464 |
NORTH CAROLINA |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 18 | 19 | 34 | 37 |
TENNESSEE |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | 1,663 | 1,648 | 3,164 | 3,324 |
VIRGINIA |  |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |  |
Electric revenue | $ 11 | $ 12 | $ 21 | $ 23 |

X
- Definition Bill credits for LTA + References No definition available. + Details
Name: | tve_BillCreditsForLTA
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Revenue from sales of electricity + References No definition available. + Details
Name: | tve_Electricrevenue
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition NES's % of operating revenues + References No definition available. + Details
Name: | tve_NESsOfOperatingRevenues
Namespace Prefix: | tve_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of LPCs signed Flexibility Agreement + References No definition available. + Details
Name: | tve_NumberOfLPCsSignedFlexibilityAgreement
Namespace Prefix: | tve_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of LPCs signed LTA + References No definition available. + Details
Name: | tve_NumberOfLPCsSignedLTA
Namespace Prefix: | tve_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Off System Sales of Electricity + References No definition available. + Details
Name: | tve_OffSystemSalesofElectricity
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Other revenue + References No definition available. + Details
Name: | tve_Otherrevenue
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Pandemic Relief Credit + References No definition available. + Details
Name: | tve_PandemicReliefCredit
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percent of sales of electricity to LPCs + References No definition available. + Details
Name: | tve_PercentOfSalesOfElectricityToLPCs
Namespace Prefix: | tve_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Sales of Electricity + References No definition available. + Details
Name: | tve_SalesofElectricity
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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 No definition available. + Details
Name: | us-gaap_EntityWideRevenueMajorCustomerLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 40 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9031-108599 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 41 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9038-108599 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-05(b)(2)) -URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(1)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
Name: | us-gaap_Revenues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | srt_MajorCustomersAxis=tve_LpcsDomain
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=tve_IndustriesdirectlyservedDomain
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=tve_FederalagenciesandotherDomain
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_AL
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_GA
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_KY
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_MS
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_NC
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_TN
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=stpr_VA
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |