v3.26.1
RELATED PARTY TRANSACTIONS (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Related Party Transaction [Line Items]      
Accounts Payable $ 158,285   $ 128,540
Operating Revenues 338,267 $ 365,736  
Related Party      
Related Party Transaction [Line Items]      
Accounts Receivables 13,000   9,000
Accounts Payable 4,000   5,000
Related Party | Common Costs, UNS Energy Affiliates      
Related Party Transaction [Line Items]      
Common costs 7,000 6,000  
Related Party | Transmission Revenues, UNS Electric      
Related Party Transaction [Line Items]      
Operating Revenues 2,000 2,000  
Related Party | Wholesale Revenues, UNS Electric      
Related Party Transaction [Line Items]      
Operating Revenues 1,000 1,000  
Related Party | Corporate Services, UNS Energy      
Related Party Transaction [Line Items]      
Corporate services $ 3,000 3,000  
Massachusetts formula - TEP's allocation (percentage) 84.00%    
Management fee $ 3,000 3,000  
Related Party | Capacity Charges , UNS Gas      
Related Party Transaction [Line Items]      
Capacity charges 1,000 1,000  
Related Party | Purchased Power, UNS Electric      
Related Party Transaction [Line Items]      
Purchased power 1,000 $ 1,000  
Related Party | UNS Energy      
Related Party Transaction [Line Items]      
Accounts Receivables 6,000   0
Accounts Payable 3,000   4,000
Related Party | UNS Electric      
Related Party Transaction [Line Items]      
Accounts Receivables 5,000   7,000
Accounts Payable 1,000   1,000
Related Party | UNS Gas      
Related Party Transaction [Line Items]      
Accounts Receivables $ 2,000   $ 2,000