v3.26.3
Borrowings and Other Financing Instruments Revolving Credit Facilities (Details) - Revolving Credit Facility [Member]
$ in Millions
9 Months Ended
Sep. 30, 2026
USD ($)
Dec. 31, 2025
USD ($)
Line of Credit Facility [Line Items]    
Credit Facility [1] $ 4,750  
Outstanding [2] 1,652  
Available 3,098  
Direct advances on the credit facility outstanding $ 0 $ 0
Number of extension you can request 2  
PSCo    
Line of Credit Facility [Line Items]    
Credit Facility [1] $ 1,200  
Outstanding [2] 48  
Available 1,152  
NSP-Minnesota    
Line of Credit Facility [Line Items]    
Credit Facility [1] 800  
Outstanding [2] 44  
Available 756  
SPS    
Line of Credit Facility [Line Items]    
Credit Facility [1] 600  
Outstanding [2] 0  
Available 600  
NSP-Wisconsin    
Line of Credit Facility [Line Items]    
Credit Facility [1] 150  
Outstanding [2] 0  
Available 150  
Xcel Energy Inc.    
Line of Credit Facility [Line Items]    
Credit Facility [1] 2,000  
Outstanding [2] 1,560  
Available $ 440  
[1] Expires in December 2029.
[2] Includes outstanding commercial paper and letters of credit.