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Background and Business Description - Additional Information (Detail) | 6 Months Ended
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Jun. 30, 2019
Background And Basis Of Presentation [Line Items] |
Entity Incorporation, Date of Incorporation | Apr. 29, 1991

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- Definition Background And Basis Of Presentation [Line Items] + References No definition available. + Details
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- Definition Date when an entity was incorporated + References No definition available. + Details
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