The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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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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No definition available.

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Unconsolidated Affiliate (Details) - USD ($)	3 Months Ended		9 Months Ended
Unconsolidated Affiliate (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Investment in unconsolidated affiliates
Equity method investment ownership interest (percent)	50.00%		50.00%
Investment in unconsolidated affiliate	$ 107,500,000		$ 107,500,000		$ 103,200,000
Equity in earnings of unconsolidated affiliate	8,500,000	$ 3,600,000	18,000,000	$ 12,100,000
Grace sales of catalysts to ART	56,100,000	76,700,000	156,400,000	194,200,000
Charges for fixed costs, research and development and selling, general and administrative services to ART	6,200,000	$ 6,000,000	18,500,000	$ 17,800,000
Grace
Investment in unconsolidated affiliates
Line of credit facility, maximum provided by Grace and Chevron each	15,000,000.0		$ 15,000,000.0
Commitment fee on credit facility (as a percent)			0.10%
Credit facility amount outstanding	0		$ 0		$ 0
Chevron
Investment in unconsolidated affiliates
Line of credit facility, maximum provided by Grace and Chevron each	$ 15,000,000.0		$ 15,000,000.0
Commitment fee on credit facility (as a percent)			0.10%