Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 481.1	$ 445.8
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2020	30.7
2021	29.4
2022	30.3
2023	30.4
2024	30.4
2025-2029	153.5
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2020	2.9
2021	2.9
2022	2.9
2023	2.9
2024	2.8
2025-2029	13.2
Expected Medicare Part D Subsidies [Abstract]
2020	0.0
2021	0.0
2022	0.0
2023	0.0
2024	0.0
2025-2029	0.1
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2020	2.9
2021	2.9
2022	2.9
2023	2.9
2024	2.8
2025-2029	$ 13.1

-- None. No documentation exists for this element. --

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in the five fiscal years thereafter (the aggregate net amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

No definition available.