Income Taxes - Difference between Income Taxes Computed At Federal Statutory Rate and Provision for (Benefit from) Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Expected benefit at U.S. Federal statutory rate					$ (1,569)	$ (1,976)
Stock-based compensation					390	297
Federal and state R&D credits					(2,111)	(909)
Deferred tax asset re-measurement due to Tax Reform						12,227
Change in valuation allowance					3,029	(9,753)
Other					105	124
Provision for (benefit from) income taxes	$ 1	$ (70)	$ 52	$ (97)	$ (156)	$ 10

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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