Organization, Business, Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Significant Accounting Policies [Line Items]
Net Income Loss	$ (12,153)	$ (7,151)
Accumulated deficit	(384,449)		$ (372,296)
Cash, cash equivalents and available-for-sale investments	$ 98,700
Pangu BioPharma [Member] \| Hong Kong [Member]
Significant Accounting Policies [Line Items]
Majority-owned subsidiary percentage	98.00%

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

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

+ References + Details