Common Costs Charged to Related Parties - Common Cost Allocations

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- Definition

Equity Contributions, Amount Approved from Parent

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- Definition

Intercompany Allocation Parent to Subsidiary

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No definition available.

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- Definition

management fee

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- Definition

Related Party Transaction, Capacity Charges

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No definition available.

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- Definition

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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-Publisher FASB
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- Definition

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Millions		3 Months Ended
	Apr. 27, 2020	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Related Party Transaction, Due to/from Related Party [Abstract]
Due from related parties		$ 11		$ 8
Due to related parties		7		4
Transmission Revenues, UNS Electric
Related Party Transaction, Due to/from Related Party [Abstract]
Revenue from related party		2	$ 1
Control Area Services, UNS Electric
Related Party Transaction, Due to/from Related Party [Abstract]
Control area services		1	1
Common Costs, UNS Energy Affiliates
Related Party Transaction, Due to/from Related Party [Abstract]
Common costs		5	5
Supplemental Workforce, SES
Related Party Transaction, Due to/from Related Party [Abstract]
Supplemental workforce		4	3
Corporate Services, UNS Energy
Related Party Transaction, Due to/from Related Party [Abstract]
Corporate services		$ 1	1
Massachusetts Formula - TEP's allocation (percentage)		83.00%
Management fee		$ 2	2
Corporate Services, UNS Energy Affiliates
Related Party Transaction, Due to/from Related Party [Abstract]
Corporate services		1	1
Capacity Charges, UNS Gas
Related Party Transaction, Due to/from Related Party [Abstract]
Capacity Charges		0	$ 1
SES
Related Party Transaction, Due to/from Related Party [Abstract]
Due to related parties		4		2
UNS Electric
Related Party Transaction, Due to/from Related Party [Abstract]
Due from related parties		5		6
Due to related parties		2		1
UNS Energy
Related Party Transaction, Due to/from Related Party [Abstract]
Due from related parties		5		0
Due to related parties		1		1
UNS Energy \| Subsequent Event
Related Party Transaction, Due to/from Related Party [Abstract]
Equity contributions amount approved from parent	$ 100
UNS Gas
Related Party Transaction, Due to/from Related Party [Abstract]
Due from related parties		$ 1		$ 2