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Employee Stock Purchase Plan - Additional Information (Detail) - 2019 ESPP [Member]	6 Months Ended
	Mar. 31, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares, discount rate	10.00%
Number of ordinary shares issued	43,934
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible employees contribution from their eligible compensation during each semi annual	1.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible employees contribution from their eligible compensation during each semi annual	15.00%
Number of ordinary shares issued	500,000

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Discount rate from fair value on offering date that participants pay for shares.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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