The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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No definition available.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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- Definition

Amount of tax benefit from exercise of option under 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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Net number of share options (or share units) granted during the period.

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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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Stock-based Compensation - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Common stock, shares authorized	50,700,000		50,700,000		50,700,000
Original term of options			10 years
Weighted average grant-date fair value of options granted			$ 4.02	$ 0.96
Tax benefit from stock based compensation expense	$ 0	$ 0	$ 0	$ 0
Restricted Stock [Member]
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Share-based payment arrangement, unrecognized stock based compensation cost	$ 4,700,000		$ 4,700,000
Performance Based Award [Member]
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Weighted-average period over which cost not yet recognized is expected to be recognized			3 years
Minimum
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Vesting period			1 year
Maximum
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Vesting period			4 years
2018 Equity Incentive Plan
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Common stock, shares authorized	2,101,478		2,101,478
Stock awards, granted			476,840		854,320