Organization and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Cumulative net losses	$ (1,130,991)	$ (986,469)

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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