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Background and Business Description - Additional Information (Detail)	3 Months Ended
	Mar. 31, 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]

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No definition available.

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- Definition

Date when an entity was incorporated

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No definition available.

+ Details

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