Total costs accrued as of the balance sheet date for environmental loss contingencies.

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=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
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-Section 50
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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 12
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount as of the balance sheet date of known and reasonably estimable amounts of recoveries from third-parties pertaining to an entity's environmental remediation obligations. An entity's balance sheet may include several assets that relate to an environmental remediation obligation. Among them are the following: a. Receivables from other potentially responsible parties that are not providing initial funding; b. anticipated recoveries from insurers; and c. anticipated recoveries from prior owners as a result of indemnification agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 30
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-Paragraph 1
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Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Loss Contingencies [Line Items]
Liabilities recognized for estimated environmental costs	$ 18.9		$ 18.9		$ 24.0
Environmental expenses	0.2	$ 0.8	4.5	$ 4.3
Receivables from insurance carriers related to environmental matters	3.9		3.9		4.1
Accounts Receivable [Member]
Loss Contingencies [Line Items]
Receivables from insurance carriers related to environmental matters	0.5		0.5		0.6
Other Noncurrent Assets [Member]
Loss Contingencies [Line Items]
Receivables from insurance carriers related to environmental matters	$ 3.4		$ 3.4		$ 3.5