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Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions | 6 Months Ended
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Jun. 30, 2019 USD ($)
Cash And Cash Equivalents And Accounts Payable |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |
Prior period reclassification adjustment | $ 23.0

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- Definition The amount of a reclassification adjustment made to prior period financial statement amounts. + References No definition available. + Details
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- Details
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