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

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Aggregate number of common shares reserved for future issuance.

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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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- Definition

Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

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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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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended		6 Months Ended	9 Months Ended
	Feb. 03, 2021	Jan. 21, 2020	Aug. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2020	Sep. 30, 2020	Dec. 31, 2020	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance				17,259,796				16,386,314
Total stock-based compensation				$ 2,931	$ 918
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Executives and employees stock options granted			1,107,250
Total stock-based compensation				800	$ 0
Total unrecognized stock-based compensation related to unvested stock options				7,900
Service Vesting Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized stock-based compensation related to unvested stock options				$ 27,700
Weighted-average period				3 years 2 months 12 days
2018 Equity Inducement Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance				1,037,500					37,500
Common shares authorized to be issued during the period	500,000					500,000
Stock option life in years							10 years
2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance				5,123,736
Common shares authorized to be issued during the period		4,312,500
Stock option life in years				10 years
Percentage threshold of outstanding shares increased annually under the plan				4.00%
Stock option grants description				the number of shares equal to 4% of the total outstanding shares of the Company’s common stock as of the immediately preceding December 31.
2008 Plan, 2015 Plan and 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares authorized to be issued during the period				945,139
Weighted-average grant date fair values of options granted				$ 11.73	$ 9.81
Issuance of common stock for exercise of stock options, Shares				21,662	0
Aggregate intrinsic value of options exercised				$ 100
Total grant date fair value of options vested				$ 3,400	$ 1,600