The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

+ Details

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

+ References

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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

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

+ References

No definition available.

+ Details

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- Definition

Expected term of share-based compensation awards, 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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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Stock-based compensation - Assumptions to determine grant-date fair value of stock options (Details) - shares	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Stock-based Compensation
Granted (in shares)			1,637,035
Employees stock options
Stock-based Compensation
Risk-free interest rate			2.12%	2.81%	2.01%
Expected term (in years)			6 years	6 years 1 month 6 days	6 years
Expected volatility			71.40%	62.00%	75.00%
Expected dividend yield			0.00%	0.00%	0.00%
Non Employee Stock Option Member
Stock-based Compensation
Risk-free interest rate					2.29%
Expected term (in years)					10 years
Expected volatility					75.00%
Expected dividend yield					0.00%
Granted (in shares)	0	0