XML 97 R69.htm IDEA: XBRL DOCUMENT v3.21.2

Fair Value Measurements Fair Value Measurements - Investments (Details) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021 USD ($) Units	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Units	Jun. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)
Investment Gains (Losses)
Financing Receivable, after Allowance for Credit Loss	$ 109		$ 109		$ 93
Balance in NDT	$ 2,800		$ 2,800
Period of time where the investor contributes capital to an investment in a private partnership - minimum | Units	3		3
Period of time where the investor contributes capital to an investment in a private partnership - maximum | Units	4		4
Minimum investment period | Units	10		10
Number of readily available quoted exchange prices for the investments	0		0
Investment funds	$ 3,968		$ 3,968		$ 3,198
LTDCP [Member]
Investment Gains (Losses)
Unrealized gains (losses) on investments	(1)	$ (2)	(1)	$ 0
SERP
Investment Gains (Losses)
Unrealized gains (losses) on investments	(3)	(7)	(8)	1
ART [Member]
Investment Gains (Losses)
Unrealized gains (losses) on investments	(48)	(97)	(168)	1
NDT [Member]
Investment Gains (Losses)
Unrealized gains (losses) on investments	(107)	$ (235)	361	$ 11
Equity Funds
Investment Gains (Losses)
NDT unfunded commitments related to private equity and real estate	231		231
Real Estate Funds
Investment Gains (Losses)
NDT unfunded commitments related to private equity and real estate	85		85
Credit [Member]
Investment Gains (Losses)
NDT unfunded commitments related to private equity and real estate	42		42
Private Equity Funds [Member]
Investment Gains (Losses)
NDT unfunded commitments related to private equity and real estate	135		135
Private real estate funds [Member]
Investment Gains (Losses)
Fair value plan assets gross	66		66
Private Credit [Member]
Investment Gains (Losses)
NDT unfunded commitments related to private equity and real estate	$ 20		$ 20

X

- References

No definition available.

+ Details

Name:	srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesReportableDataLineItems
Namespace Prefix:	srt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. This amount is not reduced by non-benefit liabilities.

+ References

No definition available.

+ Details

Name:	tve_FairValuePlanAssetsGross
Namespace Prefix:	tve_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Minimum investment period of private partnership investments.

+ References

No definition available.

+ Details

Name:	tve_Minimuminvestmentperiod
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning nuclear facilities.

+ References

No definition available.

+ Details

Name:	tve_NuclearDecommissioningFundInvestmentsFairValue
Namespace Prefix:	tve_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Number of readily available quoted exchange prices for the investments

+ References

No definition available.

+ Details

Name:	tve_NumberOfReadilyAvailableQuotedExchangePricesForInvestments
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Period of time where the investor contributes capital to an investment in a private partnership - maximum

+ References

No definition available.

+ Details

Name:	tve_Periodoftimewheretheinvestorcontributescapitaltoaninvestmentinaprivatepartnershipmaximum
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Period of time where the investor contributes capital to an investment in a private partnership - minimum

+ References

No definition available.

+ Details

Name:	tve_Periodoftimewheretheinvestorcontributescapitaltoaninvestmentinaprivatepartnershipminimum
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommitmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

+ Details

Name:	us-gaap_NotesReceivableNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of unrealized gain (loss) on investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

+ Details

Name:	us-gaap_UnrealizedGainLossOnInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_InvestmentTypeAxis=tve_LTDCPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=tve_SerpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=tve_ArtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=tve_NdtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_EquityFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_RealEstateFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_PrivateEquityFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=tve_PrivateRealEstateFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=tve_PrivateCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: