Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2025

Commitments and Contingencies Disclosure [Abstract]

Lease, Cost

Components of lease expense:

	Three Months Ended Sept. 30
(Millions of Dollars)	2025		2024
Operating leases
PPA capacity payments	$	10	$	12
Other operating leases (a)	1		1
Total operating lease expense	$	11	$	13

(a)Includes immaterial short-term lease expense.

	Nine Months Ended Sept. 30
(Millions of Dollars)	2025		2024
Operating leases
PPA capacity payments	$	28	$	38
Other operating leases (a)	3		3
Total operating lease expense	$	31	$	41

(a)Includes immaterial short-term lease expense.

Lessee, Operating Lease, Liability, Maturity

Commitments under operating leases as of Sept. 30, 2025:

(Millions of Dollars)	PPA Operating Leases		Other Operating Leases		Total Operating Leases
Total minimum obligation	$	370	$	44	$	414
Interest component of obligation	(59)		(10)		(69)
Present value of minimum obligation	$	311	$	34	345
Less current portion					(35)
Noncurrent operating lease liabilities					$	310