Pension and Savings Plans Change in Benefit Obligation, Plan Assets and Funded Status of Pension Plans (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Amounts recognized in the consolidated balance sheets:
Noncurrent asset (included in “Investments and other assets”)			$ 13.4	$ 0.0
Take-or-pay contract-based intangible recognition	$ 0.0	$ 22.5	16.6	26.7
Pension Plan
Change in benefit obligation:
Projected benefit obligation at beginning of period		874.6	853.8	795.9
Service cost	0.6	1.6	2.0	2.3
Interest cost	$ 9.7	28.0	33.5	31.4
Benefits paid			(55.6)	(55.1)
Actuarial loss (gain)			78.0	(57.3)
Projected benefit obligation at end of period		874.6	853.8	795.9
Fair value of plan assets at beginning of period			764.8	776.6
Actual return on plan assets			126.0	(18.7)
Employer contributions			20.0	62.0
Benefits paid			(55.6)	(55.1)
Fair value of plan assets at end of period		$ 776.6	855.2	764.8
Funded status at end of period			1.4	(31.1)
Amounts recognized in the consolidated balance sheets:
Noncurrent obligation (included in Other noncurrent liabilities)			(12.0)	(31.1)
Net amount recognized			$ 1.4	$ (31.1)