Accumulated Other Comprehensive Loss (Tables)

12 Months Ended

Dec. 31, 2024

Accumulated Other Comprehensive Loss [Abstract]

Reclassification out of Accumulated Other Comprehensive Loss

The following table details the reclassifications out of accumulated other comprehensive loss by component for the years ended December 31 (dollars in millions):

	Amounts Reclassified from Accumulated Other Comprehensive Loss
Details about Accumulated Other Comprehensive Loss Components (Affected Line Item in Statements of Income)	2024			2023			2022
Amortization of defined benefit pension and postretirement benefit items
Amortization of net prior service cost (a)	$	1		$	(1	)	$	(4	)
Amortization of net loss (a)		(12	)		19			57
Adjustment due to effects of regulation (a)		11			(16	)		(42	)
Total before tax (b)		—			2			11
Tax expense (b)		—			—			(2	)
Net of tax (b)	$	—		$	2		$	9

(a)These accumulated other comprehensive loss components are included in the computation of net periodic pension cost (see Note 12 for additional details).

(b)Description is also the affected line item on the Consolidated Statements of Income.