Schedule of Changes in Estimated Fair Value of Warrant Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Fair value measurements Significant unobservable inputs [Line Items]
Beginning balance	$ 40,483
Change in estimated fair value of liability classified warrants	(18,122)	$ 22,870	$ (27,632)
Ending balance	22,355	40,483
Fair Value, Measurements, Recurring [Member] \| Level 3
Fair value measurements Significant unobservable inputs [Line Items]
Beginning balance	40,483	17,613
Reclassification of derivative liability to equity upon exercise of warrants	(6)
Change in estimated fair value of liability classified warrants	(18,122)	22,870
Ending balance	$ 22,355	$ 40,483	$ 17,613

Fair Value Measurements, Significant Unobservable Inputs [Line Items]

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- Definition

Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Fair value portion of warrants not settleable in cash classified as equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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