The percentage of shares reserved for future issuance.

No definition available.

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Period Type:	instant

- Definition

Number of shares cancelled or forfeited to date under share-based payment arrangement over the life of the plan.

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Aggregate Number Of Shares Granted To Date

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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Data Type:	num:percentItemType
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Period Type:

- Details

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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Shareholders’ equity (deficit) - Share-based compensation (Details) - shares	12 Months Ended
	Dec. 31, 2019	May 08, 2019	May 07, 2019
2011 Plan
Share-based compensation
Total number of shares available for awards under the plan			2,787,063
2011 Plan \| Options \| Share-based Compensation Award, Tranche One
Share-based compensation
Percentage of shares to vest	25.00%
2011 Plan \| Options \| Share-based Compensation Award, Tranche Two
Share-based compensation
Percentage of shares to vest	2.0833%
2019 Plan
Share-based compensation
Total number of shares available for awards under the plan		4,710,564
Number of new shares available for awards under the plan		1,923,501
Percentage of shares reserved for future issuance		4.00%
2019 Plan \| Options
Share-based compensation
Total number of shares available for awards under the plan	2,316,933
Aggregate number of shares granted	287,138
Aggregate number of shares cancelled/forfeited	(66,998)
Available for future grants	2,096,793