Pension Benefits and Postretirement Benefits Other Than Pensions (Tables)

9 Months Ended

Sep. 30, 2021

Pension Plans

Defined Benefit Plan Disclosure [Line Items]

Schedule of Defined Benefit Plans Disclosures

The components of Pension (Benefit) Expense for the Pension Plan for the nine and three months ended September 30, 2021 and 2020 were:

	Nine Months Ended				Three Months Ended
(Dollars in Millions)	Sep 30, 2021		Sep 30, 2020		Sep 30, 2021		Sep 30, 2020
Interest Cost on Projected Benefit Obligation	$	5.3	$	13.5	$	1.8	$	4.5
Expected Return on Plan Assets	(7.0)		(22.0)		(2.3)		(7.3)
Amortization of Net Actuarial Loss	2.2		4.6		0.7		1.6
Total Pension (Benefit) Expense	$	0.5	$	(3.9)	$	0.2	$	(1.2)

Postretirement Benefits Other than Pensions

Defined Benefit Plan Disclosure [Line Items]

Schedule of Defined Benefit Plans Disclosures

The components of OPEB benefits for the OPEB Plans for the nine and three months ended September 30, 2021 and 2020 were:

	Nine Months Ended				Three Months Ended
(Dollars in Millions)	Sep 30, 2021		Sep 30, 2020		Sep 30, 2021		Sep 30, 2020
Service Cost	$	0.2	$	0.1	$	0.1	$	—
Interest Cost on Accumulated Postretirement Benefit Obligation	0.1		0.2		—		—
Amortization of Prior Service Credit	(1.0)		(0.9)		(0.3)		(0.2)
Amortization of Net Gain	(1.3)		(1.4)		(0.6)		(0.4)
Total OPEB (Benefit) Expense	$	(2.0)	$	(2.0)	$	(0.8)	$	(0.6)