Related Party Transactions and Transactions with Grace - Related Party Expenses and Agreements (Details) - W.R. Grace & Co. - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Indemnified receivables, tax	$ 7.1	$ 7.2
Indemnified payables, tax	$ 2.2	$ 2.7

The amount of any current tax-related balances due from affiliates as of the date of each statement of financial position presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32809-109319

+ Details

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- Definition

The amount of any current tax-related balances due to affiliates as of the date of each statement of financial position presented.

+ References

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- Definition

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.

+ References

No definition available.

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- Details

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