Leases - Components of Lease Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Fixed lease cost (Other operating expenses)	$ 5	$ 5	$ 5
Variable lease cost (Other operating expenses and Resource costs)	31	25	2
Amortization of ROU asset (Depreciation and amortization)	4	4	4
Interest on lease liabilities (Interest expense)	2	2	2
Operating Lease [Member]
Lessee, Lease, Description [Line Items]
Lease, Cost	36	30	7
Finance Lease [Member]
Lessee, Lease, Description [Line Items]
Lease, Cost	$ 6	$ 6	$ 6