Common Costs Charged to Related Parties - Common Cost Allocations

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- Definition

Intercompany Allocation Parent to Subsidiary

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- Definition

management fee

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- Definition

Proceeds from Equity Contributions from Parent

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- Definition

Related Party Transaction, Capacity Charges

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- Definition

Related Party Transaction, Number of Facilities

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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).

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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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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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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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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) $ in Thousands	1 Months Ended	12 Months Ended
RELATED PARTY TRANSACTIONS (Details) $ in Thousands	Jan. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) facility	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction, Due from (to) Related Parties [Abstract]
Receivables from Related Parties		$ 8,000	$ 8,000
Payables to Related Parties		4,000	5,000
Supplemental Workforce, SES		505,796	543,143	$ 425,555
Transmission Revenues, UNS Electric
Related Party Transaction, Due from (to) Related Parties [Abstract]
Transmission and Wholesale Revenue		7,000	6,000	7,000
Wholesale Revenues, UNS Electric
Related Party Transaction, Due from (to) Related Parties [Abstract]
Transmission and Wholesale Revenue		1,000	1,000	0
Control Area Services, UNS Electric
Related Party Transaction, Due from (to) Related Parties [Abstract]
Control Area Services and Corporate Services		4,000	3,000	3,000
Common Costs, UNS Energy Affiliates
Related Party Transaction, Due from (to) Related Parties [Abstract]
Common Costs, UNS Energy Affiliates		19,000	18,000	16,000
Corporate Services, Fortis Affiliates
Related Party Transaction, Due from (to) Related Parties [Abstract]
Corporate Services		0	0	2,000
Supplemental Workforce, SES
Related Party Transaction, Due from (to) Related Parties [Abstract]
Supplemental Workforce, SES		15,000	15,000	15,000
Corporate Services, UNS Energy
Related Party Transaction, Due from (to) Related Parties [Abstract]
Corporate Services		$ 6,000	6,000	5,000
Intercompany allocation parent to subsidiary (in percentage)		83.00%
Management fee		$ 6,000	5,000	6,000
Corporate Services, UNS Energy Affiliates
Related Party Transaction, Due from (to) Related Parties [Abstract]
Corporate Services		4,000	7,000	5,000
Capacity Charges, UNS Gas
Related Party Transaction, Due from (to) Related Parties [Abstract]
Capacity Charges, UNS Gas		$ 1,000	1,000	$ 0
Number of generation facilities \| facility		1
UNS Electric
Related Party Transaction, Due from (to) Related Parties [Abstract]
Receivables from Related Parties		$ 6,000	7,000
Payables to Related Parties		1,000	1,000
UNS Gas
Related Party Transaction, Due from (to) Related Parties [Abstract]
Receivables from Related Parties		2,000	1,000
Payables to Related Parties		0	1,000
SES
Related Party Transaction, Due from (to) Related Parties [Abstract]
Payables to Related Parties		2,000	2,000
UNS Energy
Related Party Transaction, Due from (to) Related Parties [Abstract]
Payables to Related Parties		$ 1,000	$ 1,000
UNS Energy \| Subsequent Event
Related Party Transaction, Due from (to) Related Parties [Abstract]
Equity contributions	$ 125,000