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The amount of increase (decrease) in the low and high ends of the range from previous periods actuarial study report.

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Refers to number of key officers, with whom control arrangements entered into by the entity.

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Amount of cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Number of pending claims pertaining to a loss contingency.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Commitments and Contingencies, Letters of Credit and Asbestos (Details) $ in Millions	12 Months Ended			220 Months Ended
	Dec. 31, 2019 USD ($) Claim Officer	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) Claim
Letters of Credit and Asbestos [Abstract]
Number of key officers \| Officer	1
Financial Standby Letter of Credit [Member]
Letters of Credit and Asbestos [Abstract]
Outstanding letters of credit with certain vendors	$ 3.1			$ 3.1
Asbestos [Member]
Letters of Credit and Asbestos [Abstract]
Pending claims, approximate number \| Claim	1,550			1,550
Payment for settled claims				$ 30.9
Asbestos [Member] \| Minimum [Member]
Letters of Credit and Asbestos [Abstract]
Range of possible loss	$ 52.0	$ 46.7		52.0
Incremental pre-tax provision	9.7
Increase in the range of possible loss		5.3
Asbestos [Member] \| Maximum [Member]
Letters of Credit and Asbestos [Abstract]
Range of possible loss	90.6			90.6
Increase in the range of possible loss		6.7
Asbestos [Member] \| California Case [Member]
Letters of Credit and Asbestos [Abstract]
Range of possible loss		7.6
Asbestos [Member] \| Discontinued Operations [Member]
Letters of Credit and Asbestos [Abstract]
Incremental pre-tax provision		10.1
Total operating cash outflows related to discontinued operations	(8.8)	$ (5.7)	$ (5.8)
Asbestos [Member] \| Discontinued Operations [Member] \| Minimum [Member]
Letters of Credit and Asbestos [Abstract]
Range of possible loss	50.6			50.6
Asbestos [Member] \| Discontinued Operations [Member] \| Maximum [Member]
Letters of Credit and Asbestos [Abstract]
Range of possible loss	$ 85.2			$ 85.2