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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.

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The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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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.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Accounts Receivable	$ 205,479		$ 205,479		$ 320,899
Accounts Payable	133,726		133,726		233,920
Operating Revenues	418,236	$ 439,527	854,089	$ 776,253
Other	10,000	10,000	43,000	37,000
Related Party
Related Party Transaction [Line Items]
Accounts Receivable	15,000		15,000		26,000
Accounts Payable	3,000		3,000		7,000
Related Party \| Wholesale Revenues, UNS Electric
Related Party Transaction [Line Items]
Operating Revenues	6,000	9,000	13,000	10,000
Related Party \| Common Costs, UNS Energy Affiliates
Related Party Transaction [Line Items]
Common costs	5,000	6,000	11,000	11,000
Related Party \| Transmission Revenues, UNS Electric
Related Party Transaction [Line Items]
Operating Revenues	2,000	1,000	4,000	3,000
Related Party \| Control Area Services, UNS Electric
Related Party Transaction [Line Items]
Other	1,000	1,000	1,000	2,000
Related Party \| Corporate Services, UNS Energy
Related Party Transaction [Line Items]
Corporate services	1,000	2,000	$ 4,000	5,000
Massachusetts formula - TEP's allocation (percentage)			85.00%
Management fee	2,000	2,000	$ 4,000	4,000
Related Party \| Corporate Services, UNS Energy Affiliates
Related Party Transaction [Line Items]
Corporate services	1,000	1,000	1,000	1,000
Related Party \| Purchased Power, UNS Electric
Related Party Transaction [Line Items]
Wholesale purchases	0	0	1,000	0
Related Party \| UNS Gas to TEP
Related Party Transaction [Line Items]
Capacity charges	0	$ 0	1,000	$ 0
Related Party \| UNS Electric
Related Party Transaction [Line Items]
Accounts Receivable	13,000		13,000		22,000
Accounts Payable	2,000		2,000		5,000
Related Party \| UNS Gas
Related Party Transaction [Line Items]
Accounts Receivable	2,000		2,000		2,000
Accounts Payable	1,000		1,000		1,000
Related Party \| UNS Energy
Related Party Transaction [Line Items]
Accounts Receivable	0		0		2,000
Accounts Payable	$ 0		$ 0		$ 1,000