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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
	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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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Expected To Vest Intrinsic Value

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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