The percentage of annual increase of total number of shares issued and outstanding.

No definition available.

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- Definition

Number of quarters in which the grants vest after the initial vesting in share based arrangement.

+ References

No definition available.

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- Definition

Percentage of share-based compensation awards that vest quarterly over the next twelve quarters after the initial vesting.

+ References

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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).

+ References

+ Details

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

+ Details

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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.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

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.

+ References

+ Details

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- Definition

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

+ References

+ Details

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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.

+ References

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

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

+ References

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SHARE INCENTIVE PLAN (Details) $ / shares in Units, $ in Thousands						12 Months Ended
	Oct. 24, 2018 installment $ / shares	Apr. 02, 2018 installment $ / shares shares	Mar. 14, 2018 installment $ / shares	Jul. 01, 2017 $ / shares shares	Jun. 22, 2017 installment $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 $ / shares
SHARE INCENTIVE PLAN
Ordinary shares, par value (in dollars per share)						$ 0.001	$ 0.001	$ 0.001
Share options granted (in shares) \| shares						530,757		554,000
Exercise price per share of the options granted						$ 0.001		$ 0.01
Fair value of shares granted								3.03
Weighted average grant date fair value of options granted						$ 1.69	$ 0	$ 2.69
Total fair value of options vested \| $						$ 62	$ 1,910	$ 2,990
Total intrinsic value of options exercised \| $						$ 0	$ 0	$ 0
Grant date fair value						$ 3.93	$ 4.94	$ 6.21	$ 11.05
Total fair value of nonvested shares vested \| $						$ 1,012	$ 656	$ 403
Non Vested Shares [Member]
SHARE INCENTIVE PLAN
Fair value of shares granted						$ 0	$ 0	$ 3.03
Vested and exercisable upon 1st anniversary year
SHARE INCENTIVE PLAN
Vesting of share-based compensation (as a percent)						25.00%		25.00%
Vested quarterly in twelve quarters with equal quarterly installments
SHARE INCENTIVE PLAN
Vesting of share-based compensation (as a percent)						75.00%		75.00%
Board of Directors
SHARE INCENTIVE PLAN
Share options granted (in shares) \| shares					1,286,878
Exercise price per share of the options granted					$ 11.66
Employees
SHARE INCENTIVE PLAN
Share options granted (in shares) \| shares		20,000				530,757		554,000
Exercise price per share of the options granted		$ 0.01				$ 0.001		$ 0.001
Vesting of share-based compensation (as a percent)		25.00%
Shares vesting quarterly in twelve quarters (as a percent)		75.00%
Number of quarters of vesting \| installment		12
Contract term						10 years		10 years
Director and consultant
SHARE INCENTIVE PLAN
Share options granted (in shares) \| shares				50,300
Exercise price per share of the options granted				$ 1.48
Directors and executive officers \| Non Vested Shares [Member]
SHARE INCENTIVE PLAN
Vesting of share-based compensation (as a percent)			25.00%
Shares vesting quarterly in twelve quarters (as a percent)			75.00%
Number of quarters of vesting \| installment			12
Grant date fair value			$ 20.43
Non-employees \| Non Vested Shares [Member]
SHARE INCENTIVE PLAN
Vesting of share-based compensation (as a percent)	25.00%
Shares vesting quarterly in twelve quarters (as a percent)	75.00%
Number of quarters of vesting \| installment	12
Grant date fair value	$ 17.11
Completion of IPO before June 22, 2018 \| Board of Directors
SHARE INCENTIVE PLAN
Vesting of share-based compensation (as a percent)					25.00%
Shares vesting quarterly in twelve quarters (as a percent)					75.00%
Number of quarters of vesting \| installment					12
Non completion of IPO before June 22, 2018 \| Board of Directors
SHARE INCENTIVE PLAN
Vesting of share-based compensation (as a percent)					25.00%
Shares vesting quarterly in twelve quarters (as a percent)					75.00%
Number of quarters of vesting \| installment					12
Completion of IPO on September 27, 2018 \| Employees
SHARE INCENTIVE PLAN
Share options granted (in shares) \| shares					772,127
Exercise price per share of the options granted					$ 11.66
Vesting of share-based compensation (as a percent)					25.00%
Shares vesting quarterly in twelve quarters (as a percent)					75.00%
Number of quarters of vesting \| installment					12
2009 Share Incentive Plan
SHARE INCENTIVE PLAN
Total number shares authorized \| shares						2,573,756
Ordinary shares, par value (in dollars per share)						$ 0.001
2017 Share Incentive Plan
SHARE INCENTIVE PLAN
Total number shares authorized \| shares						2,059,005
Additional annual increase in number of shares (as a percent)						2.00%