Income Taxes - Schedule of Deferred Income Taxes, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Depreciable assets	$ (5,106)	$ (1,964)
Deferred revenue	2,130	2,029
Accruals and reserves	1,572	1,858
Stock-based compensation	1,997	2,232
Impaired strategic investments	1,782	1,767
NOL carryforwards	4,319	3,526
U.S. Federal and state R&D credits	3,066	3,216
Other	618	897
Valuation allowance	(7,253)	(6,246)
Deferred taxes, net	$ 3,125	$ 7,315

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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