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Schedule of Restricted Stock Unit Awards Aggregate Intrinsic Value (Detail) - Restricted Stock Units - USD ($) $ / shares in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Vested | $ 71,582 | $ 46,110 | $ 63,688
Outstanding | $ 214,509 | $ 154,752 | $ 77,015
Expected to vest | $ 210,301 | $ 152,374 | $ 77,187

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Expected To Vest Intrinsic Value + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options. + References No definition available. + Details
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- Definition Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options. + References No definition available. + Details
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- Details
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