Fair value of options vested per share.

No definition available.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of unvested options outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of vested options outstanding.

+ References

No definition available.

+ Details

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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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.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ 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 (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ 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

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ 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 (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

+ 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Shareholders’ equity (deficit) - Share-based compensation - Outstanding and exercisable options (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2017 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, Options outstanding \| shares		2,295,045	2,584,666
Weighted average remaining contractual life (years), Options outstanding	7 years 9 months 18 days	8 years 7 months 6 days
Weighted average exercise price, Options outstanding		$ 1.771	$ 3.755	$ 1.133
Number of options, Options exercisable \| shares			1,213,391
Weighted average remaining contractual life (years), Options exercisable	7 years
Weighted average exercise price, Options exercisable		$ 1.314	$ 1.652
Intrinsic value of option \| $			$ 32.7
Fair value of common share (in dollars per share)			$ 16.01
Intrinsic value of options vested \| $			$ 17.4
Intrinsic value of options non vested \| $			$ 15.5
C$0.96
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)	$ 0.96
Number of options, Options outstanding \| shares			235,497
Weighted average remaining contractual life (years), Options outstanding	3 years 3 months 18 days
Weighted average exercise price, Options outstanding	$ 0.914
Number of options, Options exercisable \| shares			235,497
Weighted average remaining contractual life (years), Options exercisable	3 years 3 months 18 days
Weighted average exercise price, Options exercisable	$ 0.914
$1.12
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 1.12
Number of options, Options outstanding \| shares			261,913
Weighted average remaining contractual life (years), Options outstanding	6 years 3 months 18 days
Weighted average exercise price, Options outstanding			$ 1.117
Number of options, Options exercisable \| shares			207,319
Weighted average remaining contractual life (years), Options exercisable	6 years 2 months 12 days
Weighted average exercise price, Options exercisable			$ 1.117
$1.54
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 1.54
Number of options, Options outstanding \| shares			956,688
Weighted average remaining contractual life (years), Options outstanding	7 years 10 months 24 days
Weighted average exercise price, Options outstanding			$ 1.543
Number of options, Options exercisable \| shares			429,175
Weighted average remaining contractual life (years), Options exercisable	7 years 10 months 24 days
Weighted average exercise price, Options exercisable			$ 1.543
$1.91
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 1.91
Number of options, Options outstanding \| shares			82,772
Weighted average remaining contractual life (years), Options outstanding	8 years 7 months 6 days
Weighted average exercise price, Options outstanding			$ 1.915
Number of options, Options exercisable \| shares			40,122
Weighted average remaining contractual life (years), Options exercisable	9 years
Weighted average exercise price, Options exercisable			$ 2.000
$2.66
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 2.66
Number of options, Options outstanding \| shares			710,914
Weighted average remaining contractual life (years), Options outstanding	8 years 10 months 24 days
Weighted average exercise price, Options outstanding			$ 2.660
Number of options, Options exercisable \| shares			300,113
Weighted average remaining contractual life (years), Options exercisable	8 years 10 months 24 days
Weighted average exercise price, Options exercisable			$ 2.660
$9.42
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 9.42
Number of options, Options outstanding \| shares			116,742
Weighted average remaining contractual life (years), Options outstanding	9 years 2 months 12 days
Weighted average exercise price, Options outstanding			$ 9.415
$15.87
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 15.87
Number of options, Options outstanding \| shares			23,620
Weighted average remaining contractual life (years), Options outstanding	9 years 7 months 6 days
Weighted average exercise price, Options outstanding			$ 15.870
$17.78
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 17.78
Number of options, Options outstanding \| shares			42,000
Weighted average remaining contractual life (years), Options outstanding	9 years 10 months 24 days
Weighted average exercise price, Options outstanding			$ 17.780
Number of options, Options exercisable \| shares			1,165
Weighted average remaining contractual life (years), Options exercisable	9 years 10 months 24 days
Weighted average exercise price, Options exercisable			$ 17.780
$19.14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 19.14
Number of options, Options outstanding \| shares			3,760
Weighted average remaining contractual life (years), Options outstanding	9 years 9 months 18 days
Weighted average exercise price, Options outstanding			$ 19.140
$21.28
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 21.28
Number of options, Options outstanding \| shares			3,760
Weighted average remaining contractual life (years), Options outstanding	9 years 8 months 12 days
Weighted average exercise price, Options outstanding			$ 21.280
$22.45
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 22.45
Number of options, Options outstanding \| shares			147,000
Weighted average remaining contractual life (years), Options outstanding	9 years 8 months 12 days
Weighted average exercise price, Options outstanding			$ 22.450