PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Tables)

6 Months Ended

Jun. 30, 2024

Retirement Benefits [Abstract]

Schedule of Components in Net Periodic Benefit Cost (Credit)

Components of Net Periodic Benefit Cost (Credit)	Pension		Other Postretirement
	2024	2023	2024	2023
Millions
Quarter Ended June 30,
Service Cost	$1.7	$1.6	$0.4	$0.5
Non-Service Cost Components (a)
Interest Cost	9.6	10.1	0.9	1.5
Expected Return on Plan Assets	(11.2)	(11.0)	(2.8)	(2.8)
Amortization of Prior Service Credits	—	—	(2.9)	(1.7)
Amortization of Net Loss (Gain)	1.6	1.5	(0.8)	(0.6)
Net Periodic Benefit Cost (Credit)	$1.7	$2.2	$(5.2)	$(3.1)
Six Months Ended June 30,
Service Cost	$3.3	$3.2	$0.8	$1.1
Non-Service Cost Components (a)
Interest Cost	19.3	20.2	1.9	3.0
Expected Return on Plan Assets	(22.4)	(21.9)	(5.6)	(5.6)
Amortization of Prior Service Credits	—	—	(5.8)	(3.5)
Amortization of Net Loss (Gain)	3.2	2.9	(1.6)	(1.1)
Net Periodic Benefit Cost (Credit)	$3.4	$4.4	$(10.3)	$(6.1)

(a)These components of net periodic benefit cost (credit) are included in the line item “Other” under Other Income (Expense) on the Consolidated Statement of Income.