Retirement Benefits (Tables)

9 Months Ended

Sep. 30, 2022

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Schedule of net pension and retiree health benefit (income) cost

Net pension and retiree health benefit (income) cost included the following components:

	Defined Benefit Pension Plans
	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Components of net periodic benefit cost:
Service cost	$	87.1	$	92.5	$	264.4	$	277.8
Interest cost	98.9		84.5		299.0		253.6
Expected return on plan assets	(235.1)		(237.5)		(711.6)		(712.7)
Amortization of prior service cost	0.6		1.0		1.9		3.2
Recognized actuarial loss	85.3		121.9		256.8		366.3
Net periodic benefit cost	$	36.8	$	62.4	$	110.5	$	188.2

	Retiree Health Benefit Plans
	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Components of net periodic benefit income:
Service cost	$	11.7	$	12.4	$	35.0	$	37.0
Interest cost	9.4		8.1		28.4		24.4
Expected return on plan assets	(38.0)		(36.5)		(114.1)		(109.6)
Amortization of prior service benefit	(13.7)		(14.9)		(41.1)		(44.7)
Recognized actuarial loss	0.2		0.8		0.7		2.4
Net periodic benefit income	$	(30.4)	$	(30.1)	$	(91.1)	$	(90.5)