Contingencies (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) Defendant Site	Dec. 31, 2018 USD ($)
Environmental Matters [Abstract]
Number of on-site cleanups \| Site	4
Number of on-site cleanups in operation and maintenance stage \| Site	3
Number of on-site cleanups in implementation stage \| Site	1
Undiscounted accrued liabilities \| $	$ 6.8	$ 6.9
Asbestos and Silica Related Litigation [Member]
Asbestos and Silica Related Litigation [Abstract]
Litigation reserve \| $	102.3	105.8
Insurance recovery receivable amount \| $	$ 102.8	$ 103.0
Asbestos and Silica Related Litigation [Member] \| Minimum [Member]
Asbestos and Silica Related Litigation [Abstract]
Number of defendants \| Defendant	25

The number of on-site cleanups for which the Company is the primary responsible party.

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The number of on-site cleanups for which the Company is the primary responsible party in the implementation stage.

+ References

No definition available.

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The number of on-site cleanups for which the Company is the primary responsible party in the operation and maintenance stage.

+ References

No definition available.

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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- References

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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Number of defendants named in a legal action.

+ References

No definition available.

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