Borrowings and Other Financing Instruments (Tables)

9 Months Ended

Sep. 30, 2024

Borrowings and Other Financing Instruments [Abstract]

Credit Facilities

As of Sept. 30, 2024, SPS had the following committed revolving credit facility available (in millions of dollars):

Credit Facility (a)		Drawn (b)		Available
$	500	$	—	$	500

(a)Expires in September 2027.

(b)Includes outstanding letters of credit.

Money Pool

Borrowings and Other Financing Instruments [Abstract]

Short-Term Borrowings

Money pool borrowings:

(Amounts in Millions, Except Interest Rates)	Three Months Ended Sept. 30, 2024		Year Ended Dec. 31, 2023
Borrowing limit	$	100	$	100
Amount outstanding at period end	—		27
Average amount outstanding	—		46
Maximum amount outstanding	—		100
Weighted average interest rate, computed on a daily basis	N/A		5.04		%
Weighted average interest rate at period end	N/A		5.34

Commercial Paper

Borrowings and Other Financing Instruments [Abstract]

Short-Term Borrowings

Commercial paper outstanding:

(Amounts in Millions, Except Interest Rates)	Three Months Ended Sept. 30, 2024		Year Ended Dec. 31, 2023
Borrowing limit	$	500	$	500
Amount outstanding at period end	—		75
Average amount outstanding	—		50
Maximum amount outstanding	—		119
Weighted average interest rate, computed on a daily basis	N/A		5.12		%
Weighted average interest rate at period end	N/A		5.56