Name:	tve_DefinedBenefitPlanActualRateOfReturnOnPlanAssets
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An assumption, maintained for the future, as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

No definition available.

Name:	tve_DefinedBenefitPlanAssumptionsMaintainedForCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
Namespace Prefix:	tve_
Data Type:	num:percentItemType
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The high end of the range for compensation increases for defined benefit plans as determined by company compensation experience study.

No definition available.

Name:	tve_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncreaseHighEndOfRange
Namespace Prefix:	tve_
Data Type:	num:percentItemType
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The low end of the range for compensation increases for defined benefit plans as determined by company compensation experience study.

No definition available.

Name:	tve_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncreaseLowEndOfRange
Namespace Prefix:	tve_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The cost of living adjustment percentage used for defined benefit plans.

No definition available.

Name:	tve_DefinedBenefitPlanCostOfLivingAdjustmentAssumption
Namespace Prefix:	tve_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Minimum percentage increase in twelve-month average CPI-U necessary to receive COLA.

No definition available.

Name:	tve_MinimumpercentageincreaseintwelvemonthaverageCPIUnecessarytoreceiveCOLA
Namespace Prefix:	tve_
Data Type:	num:percentItemType
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Number of years during which cost of living adjustment changed.

No definition available.

Name:	tve_NumberOfYearsDuringWhichCostOfLivingAdjustmentChanged
Namespace Prefix:	tve_
Data Type:	us-types:durationStringItemType
Balance Type:	na
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The period in which an actual compensation experience study is performed at TVA to determine assumptions related to compensation increases for defined benefit plans.

No definition available.

Name:	tve_PeriodDuringWhichActualCompanyCompensationExperienceStudyPerformed
Namespace Prefix:	tve_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Rate of inflation.

No definition available.

Name:	tve_Rateofinflation
Namespace Prefix:	tve_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Retirement age of eligibility for cost of living adjustment after January 1, 2010.

No definition available.

Name:	tve_RetirementAgeOfEligibilityForCostOfLivingAdjustmentAfterJanuary12010
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
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Period Type:	duration

Retirement age of eligibility for cost of living adjustment before January 1, 2010.

No definition available.

Name:	tve_RetirementageofeligibilityforcostoflivingadjustmentbeforeJanuary12010
Namespace Prefix:	tve_
Data Type:	xbrli:integerItemType
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The interest rate used to adjust for the time value of money for the plan.

Name:	us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	instant

Expected rate of compensation increases (for pay-related plans).

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The interest rate used to adjust for the time value of money.

Name:	us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Expected rate of compensation increases (for pay-related plans).

Name:	us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

Name:	us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The ultimate trend rate for health care costs.

Name:	us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.