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Litigation (Details) - USD ($) $ in Millions	Nov. 03, 2016	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Loss Contingencies [Line Items]
Potential liabilities related to litigation and environmental matters		$ 34.3	$ 31.8	$ 20.0
Litigation [Domain]
Loss Contingencies [Line Items]
Loss contingency, damages awarded, value	$ 44.8

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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Amount of damages awarded to the plaintiff in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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