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Commitments and Contingencies - Additional Information (Detail) - USD ($) |  |  | 1 Months Ended |
--- | --- | --- | --- | ---
May 08, 2018 | Jan. 05, 2018 | Mar. 31, 2018 | Sep. 30, 2018
Commitments And Contingencies [Line Items] |  |  |  |
Letters of credit outstanding, amount |  |  |  | $ 7,800,000
Outstanding guarantees |  |  |  | 0
Contingently liable for performance, current |  |  |  | $ 27,700,000
American Gypsum Company LLC [Member] | Homebuilder Settlement Agreement [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Litigation settlement amount | $ 6,000,000 |  |  |
American Gypsum Company LLC [Member] | Direct and Indirect Purchaser Class [Member] | Direct and Indirect Purchaser Settlement Agreements [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Litigation settlement amount |  | $ 39,100,000 |  |
Amount deposited to qualified settlement fund |  |  | $ 38,800,000 |

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- Definition Amount deposited to qualified settlement fund. + References No definition available. + Details
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- Definition Commitments and contingencies. + References No definition available. + Details
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- Definition Contingent liability for performance bonds required by states municipalities and related agencies. + References No definition available. + Details
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- Definition This item represents a non-contingent liability for the fair value of an obligation to stand ready to perform over the term of a guaranty issued in the event that specified triggering events or conditions occur. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913062&loc=d3e11019-110243 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 25 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82913062&loc=d3e11049-110243 + Details
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition Amount awarded to other party in judgment or settlement of litigation. + References No definition available. + Details
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- Details
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