Approved Recovery of Spending Budget

No definition available.

Name:	tep_ApprovedRecoveryofSpendingBudget
Namespace Prefix:	tep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Approved Renewable Energy Standard Increase In Tariff Amount

+ References

No definition available.

+ Details

Name:	tep_ApprovedRenewableEnergyStandardIncreaseInTariffAmount
Namespace Prefix:	tep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Approved Spending Budget

+ References

No definition available.

+ Details

Name:	tep_ApprovedSpendingBudget
Namespace Prefix:	tep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Year over year cap on Increase in Lost Fixed Cost Recovery rate.

+ References

No definition available.

+ Details

Name:	tep_CapOnIncreaseInLostFixedCostRecoveryRate
Namespace Prefix:	tep_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Deferred Fuel And Purchased Power Costs

+ References

No definition available.

+ Details

Name:	tep_DeferredFuelAndPurchasedPowerCosts
Namespace Prefix:	tep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Energy Efficiency Implementation Plan Term

+ References

No definition available.

+ Details

Name:	tep_EnergyEfficiencyImplementationPlanTerm
Namespace Prefix:	tep_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Months approved rate in effect unless modified in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	tep_MonthsApprovedRateInEffectUnlessModified
Namespace Prefix:	tep_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Purchased Power And Fuel Adjustment, Refunds (Recoveries)

+ References

No definition available.

+ Details

Name:	tep_PurchasedPowerAndFuelAdjustmentRefundsRecoveries
Namespace Prefix:	tep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Regulatory Assets [Roll Forward]

+ References

No definition available.

+ Details

Name:	tep_RegulatoryAssetsRollForward
Namespace Prefix:	tep_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Renewable Energy Target, Percentage

+ References

No definition available.

+ Details

Name:	tep_RenewableEnergyTargetPercentage
Namespace Prefix:	tep_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The net amount of all regulatory assets less all regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

+ Details

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

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

- Details

Name:	tep_TriggeringEventAxis=tep_Effective11202412312026Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PublicUtilitiesRegulatoryProceedingAxis=tep_PurchasedPowerandFuelAdjustmentClauseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PublicUtilitiesRegulatoryProceedingAxis=us-gaap_RenewableEnergyProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PublicUtilitiesRegulatoryProceedingAxis=tep_EnergyEfficiencyStandardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PublicUtilitiesRegulatoryProceedingAxis=tep_LostFixedCostRecoveryMechanismMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

REGULATORY MATTERS (Cost Recovery Mechanisms) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	May 31, 2024	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2023
Effective 1/1/2024-12/31/2026
Regulatory Assets [Roll Forward]
Energy efficiency implementation plan term					3 years
Purchased Power and Fuel Adjustment Clause
Public Utilities, General Disclosures [Line Items]
Months approved rate in effect unless modified		12 months
Regulatory Assets [Roll Forward]
Beginning of Period		$ (32)	$ (49)	$ (49)
Deferred Fuel and Purchased Power Costs		68	61
PPFAC and Base Power Recoveries		(52)	(60)
End of Period		$ (16)	$ (48)	$ (32)
Renewable Energy Standard
Regulatory Assets [Roll Forward]
Renewable energy target percentage				15.00%
Approved spending budget	$ 66
Approved renewable energy standard increase in tariff amount	$ 17
Energy Efficiency Standards \| Effective 1/1/2024-12/31/2026
Regulatory Assets [Roll Forward]
Approved recovery of spending budget					$ 72
Lost Fixed Cost Recovery
Regulatory Assets [Roll Forward]
Cap on increase in lost fixed cost recovery rate (percentage)		2.00%