Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made 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).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Stock options - Restricted stock units (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Jan. 31, 2020	Jul. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Restricted stock units
Share-based compensation expense			$ 1,609	$ 1,164
Restricted stock units
Restricted stock units
Vesting period (in years)	4 years	2 years
Number of Shares, Unvested, Beginning of period (in shares)	324,932		324,932
Number of Shares, Granted (in shares)	324,932
Number of Shares, Vested (in shares)			(12,075)
Number of Shares, Forfeited (in shares)			760,193
Share-based compensation expense			$ 310