XML 94 R74.htm IDEA: XBRL DOCUMENT
v3.22.4

Risk Management Activities and Derivative Transactions Counterparty Credit Risk (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Dec. 31, 2022 USD ($) Customers | Sep. 30, 2022 USD ($)
Derivative |  |
Accounts Receivable, before Allowance for Credit Loss, Current | $ | $ 1,633 | $ 1,899
Total derivatives not subject to master netting or similar arrangement | $ | $ 80 | $ 152
Two Largest Customer Percentage of Total Operating Revenue | 1600.00% |
Moody's, A1 Rating [Member] |  |
Derivative |  |
Banking Counterparties Credit Rating | A2 |
Natural Gas Banking Counterparties Credit Rating | A1 |
Moody's, Caa1 Rating [Member] |  |
Derivative |  |
Natural Gas Banking Counterparties Credit Rating | B1 |
Credit of Customers |  |
Derivative |  |
Number of customers that represent the percent of sales | Customers | 2 |
Number of customers that represent the percent of sales | Customers | 2 |

X
- Definition Banking Counterparties Credit Rating + References No definition available. + Details
Name: | tve_BankingCounterpartiesCreditRating
Namespace Prefix: | tve_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Natural Gas Banking Counterparties Credit Rating + References No definition available. + Details
Name: | tve_NaturalGasBankingCounterpartiesCreditRating
Namespace Prefix: | tve_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of customers that represent the percent of sales + References No definition available. + Details
Name: | tve_Numberofcustomersthatrepresentthepercentofsales
Namespace Prefix: | tve_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition This concept explains the total percentage of operating revenue provided by the two largest customers. + References No definition available. + Details
Name: | tve_TwoLargestCustomerPercentageOfTotalOperatingRevenue
Namespace Prefix: | tve_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 9 -URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4531-111522 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)(a)(1)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_AccountsReceivableGrossCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 + Details
Name: | us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_CreditRatingMoodysAxis=srt_MoodysA1RatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingMoodysAxis=srt_MoodysCaa1RatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=tve_CreditOfCustomersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |