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Revenue Recognition - Additional Information (Detail) $ in Thousands | Dec. 31, 2018 USD ($)
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Revenue From Contract With Customer [Line Items] |
Net contract assets (liabilities) | $ 93,194
ASU 2014-09 | Increase in Net Contract Assets (Liabilities) |
Revenue From Contract With Customer [Line Items] |
Net contract assets (liabilities) | $ 8,568

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