Retirement Benefits (Tables)

3 Months Ended

Mar. 31, 2020

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 March 31,
	2020			2019
Components of net periodic benefit cost:
Service cost	$	78.7		$	61.8
Interest cost	105.0			120.7
Expected return on plan assets	(221.2		)	(211.1		)
Amortization of prior service cost	1.1			1.5
Recognized actuarial loss	111.0			69.6
Net periodic benefit cost	$	74.6		$	42.5

	Retiree Health Benefit Plans
	Three Months Ended March 31,
	2020			2019
Components of net periodic benefit income:
Service cost	$	9.8		$	8.8
Interest cost	11.0			14.6
Expected return on plan assets	(37.4		)	(36.0		)
Amortization of prior service benefit	(14.9		)	(15.7		)
Recognized actuarial loss	0.8			0.5
Net periodic benefit income	$	(30.7	)	$	(27.8	)