Common Shares - Unrecognized Compensation (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock options	$ 159
Weighted average unrecognized compensation recognition period	1 year 1 month 6 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested awards	$ 210
Weighted average unrecognized compensation recognition period	8 months 12 days
Phantom Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested awards	$ 117
Weighted average unrecognized compensation recognition period	1 year 6 months

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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