Equity Conversion Ratio

No definition available.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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Nature of the Business (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Jun. 26, 2018 $ / shares shares	Jun. 22, 2018 USD ($)	Sep. 30, 2018 USD ($) $ / shares	Sep. 30, 2017 USD ($) $ / shares	Sep. 30, 2016 USD ($)	Jun. 22, 2018 £ / shares	Jun. 22, 2018 $ / shares	Sep. 30, 2015 USD ($)
Class of Stock
Equity conversion ratio		3.185
Net loss			$ 44,751	$ 19,727	$ 12,550
Accumulated deficit			92,653	47,902
Cash			$ 247,089	$ 137,070	$ 28,059			$ 10,203
Ordinary shares
Class of Stock
Common stock, par value (usd/gbp per share) \| (per share)			$ 0.000042	$ 0.000042		£ 0.000032	$ 0.000042
Ordinary shares \| IPO
Class of Stock
Number of shares issued in transaction (shares) \| shares	10,147,059
Per share price of issuance (usd per share) \| $ / shares	$ 17.00
Proceeds of issuance of ordinary shares, net of issuance costs		$ 156,500
Ordinary shares \| Options
Class of Stock
Number of shares issued in transaction (shares) \| shares	1,323,529