Leases (Tables)

12 Months Ended

Dec. 31, 2024

Leases [Abstract]

Components of Lease Expense

The components of lease expense were as follows for the year ended December 31 (dollars in millions):

	2024		2023		2022
Operating lease cost:
Fixed lease cost (Other operating expenses)	$	5	$	5	$	5
Variable lease cost (Other operating expenses and Resource costs)		31		25		2
Total operating lease cost	$	36	$	30	$	7
Finance lease cost:
Amortization of ROU asset (Depreciation and amortization)	$	4	$	4	$	4
Interest on lease liabilities (Interest expense)		2		2		2
Total finance lease cost	$	6	$	6	$	6

Summary of Supplemental Cash Flow Information related to Leases

Supplemental cash flow information related to leases was as follows for the year ended December 31 (dollars in millions):

	2024		2023		2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflows:
Operating lease payments	$	5	$	5	$	5
Interest on finance lease		2		2		2
Total operating cash outflows	$	7	$	7	$	7
Finance cash outflows:
Principal payments on finance lease	$	3	$	3	$	3

Summary of Supplemental Balance Sheet Information Related to Leases

Supplemental balance sheet information related to leases was as follows for December 31 (dollars in millions):

	December 31,			December 31,
	2024			2023
Operating Leases
Operating lease ROU assets (Other property and investments-net    and other non-current assets)	$	66		$	68
Other current liabilities	$	4		$	4
Other non-current liabilities and deferred credits		62			64
Total operating lease liabilities	$	66		$	68
Finance Leases
Finance lease ROU assets (Other property and investments-net    and other non-current assets)	$	33		$	36
Other current liabilities	$	4		$	3
Other non-current liabilities and deferred credits		35			39
Total finance lease liabilities	$	39		$	42
Weighted Average Remaining Lease Term
Operating leases	21 years			22 years
Finance leases	4 years			5 years
Weighted Average Discount Rate
Operating leases		4.30	%		4.29	%
Finance leases		3.46	%		3.77	%

Summary of Maturities of Lease Liabilities

Maturities of lease liabilities (including principal and interest) were as follows as of December 31, 2024 (dollars in millions):

	Operating Leases			Finance Leases
2025	$	5		$	5
2026		5			5
2027		5			5
2028		5			6
2029		5			6
Thereafter		79			22
Total lease payments	$	104		$	49
Less: imputed interest		(38	)		(10	)
Total	$	66		$	39

Summary of Maturities of Lease Liabilities

Maturities of lease liabilities (including principal and interest) were as follows as of December 31, 2024 (dollars in millions):

	Operating Leases			Finance Leases
2025	$	5		$	5
2026		5			5
2027		5			5
2028		5			6
2029		5			6
Thereafter		79			22
Total lease payments	$	104		$	49
Less: imputed interest		(38	)		(10	)
Total	$	66		$	39