Contingencies (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($) Defendant Site	Dec. 31, 2017 USD ($)
Asbestos and Silica Related Litigation [Abstract]
Insurance recoveries of legal defense costs	$ 5.6
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	$ 7.1	$ 7.5
Asbestos and Silica Related Litigation [Member]
Asbestos and Silica Related Litigation [Abstract]
Litigation reserve	100.8	105.6
Insurance recovery receivable amount	96.2	$ 100.4
Asbestos related insurance recoveries	9.6
Recovery of indemnity payments	4.0
Insurance recoveries of legal defense costs	$ 5.6
Asbestos and Silica Related Litigation [Member] \| Minimum [Member]
Asbestos and Silica Related Litigation [Abstract]
Number of defendants \| Defendant	25

Represents insurance recoveries of asbestos legal fees during the period.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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.

+ Details

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- Definition

The amount recovered from insurance indemnity payments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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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

No definition available.

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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- Definition

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
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	debit
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- Definition

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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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- References

No definition available.

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- Definition

Number of defendants named in a legal action.

+ References

No definition available.

+ Details

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