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The Company and Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended
	Sep. 30, 2019 USD ($) ClinicalTrials	Jun. 30, 2019 USD ($)
Targeted or Tracking Stock, Stock [Line Items]
Number of clinical stage candidates | ClinicalTrials	4
Number of candidate in an ongoing global registration trial | ClinicalTrials	1
Unrecognized tax benefits		$ 0
Accumulated Losses Since Inception	$ (234,212,000)	$ (231,218,000)
Cash And Cash Equivalents,Short Term Investments And Common Stock Proceeds Receivable	$ 65,900,000

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