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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Amount of noncash expense for share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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Gross number of share options (or share units) granted during the period.

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Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of award under share-based payment arrangement.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Share-Based Compensation - Additional Information (Details)				3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 06, 2020 $ / shares shares	Jan. 08, 2020 $ / shares shares	Jun. 07, 2018 item $ / shares shares	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2019 USD ($) $ / shares	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual life of options, outstanding						8 years 2 months 27 days		8 years 5 months 12 days
Fair value of options Vested				$ 3,833,603	$ 2,483,808	$ 5,484,528	$ 3,874,750
Weighted average grant date fair value of options granted \| $ / shares						$ 13.85	$ 12.70
Share options granted during the period \| shares						1,438,500
Share-based compensation						$ 10,738,950	$ 7,321,114
Total share-based compensation				5,056,069	4,386,123	10,738,950	7,321,114
Excess Tax Benefit from Share-based Compensation, Operating Activities						0	0
Excess Tax Benefit from Share-based Compensation, Financing Activities						$ 0	0
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual life of options, outstanding						10 years
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation				3,591,838	3,523,152	$ 7,856,928	5,623,829
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation				1,464,231	862,971	$ 2,882,022	1,697,285
Restricted ordinary shares subject to forfeiture [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fully-diluted outstanding shares			5.00%
Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period expected to realize unrecognized compensation expense						3 years 8 months 12 days
Total compensation expense not yet recognized relating to unvested RSUs				9,629,359		$ 9,629,359
Total share-based compensation				681,846		1,280,141
Restricted share units \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation				640,722		1,228,051
Restricted share units \| Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation				41,124		52,090
Share options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unvested options compensation expense not yet recognized				29,117,903		$ 29,117,903
Period expected to realize unrecognized compensation expense						4 years
Senior Management [Member] \| Restricted ordinary shares subject to forfeiture [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.33%
Ordinary shares awarded, per share \| $ / shares			$ 15.00
Ordinary shares \| shares			1,306,348
Number of quarters for vesting \| item			8
Share-based compensation				2,969,162	4,112,927	$ 6,545,688	7,885,577
Senior Management [Member] \| Restricted ordinary shares subject to forfeiture [Member] \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation				$ 1,273,690	$ 1,632,930	$ 2,906,620	$ 3,265,860
Senior Management [Member] \| Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options granted during the period \| shares		505,000
Ordinary shares awarded, per share \| $ / shares		$ 20.30
Consultant \| Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options granted during the period \| shares	40,000
Ordinary shares awarded, per share \| $ / shares	$ 16.45
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						36 months
First Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						25.00%
Second Anniversary [Member] \| Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						50.00%
Third Anniversary [Member] \| Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						25.00%
Fourth Anniversary [Member] \| Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage						25.00%
Over Three Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						36 months