Common Shares - Summary Of Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments Related to Tax Withholding for Share-based Compensation	$ 97	$ 46
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, Number of units, beginning of period (in shares)	1,491,301	1,002,670	1,002,670
Granted, Number of units (in shares)	1,609,000		1,412,500
Cancelled/forfeited, Number of units (in shares)	(211,019)		(657,573)
Vested, net of shares withheld, Number of units (in shares)	(316,313)		(266,296)
Unvested, Number of units, end of period (in shares)	2,572,969		1,491,301
Unvested, weighted average fair value, beginning of year (in dollars per share)	$ 0.51	$ 0.78	$ 0.78
Granted, Weighted average fair value (in dollars per share)	0.41		0.49
Cancelled/forfeited, Weighted average fair value (in dollars per share)	0.57		0.76
Vested, Weighted average fair value (in dollars per share)	0.57		0.84
Unvested, weighted average fair value, end of year (in dollars per share)	$ 0.43		$ 0.51
Payments Related to Tax Withholding for Share-based Compensation	$ 97,000	$ 46,000

Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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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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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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).

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

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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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