Shareholders' Equity (Phantom Share Units) (Details) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($)
Fair Value Assumptions
Current accrued liabilities \| $	$ 4,171	$ 3,129
Phantom Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Number of Phantom Share Units (000's)
Beginning balance (in shares) \| shares	1,350
Issued (in shares) \| shares	346
Vested (in shares) \| shares	(601)
Expired / Forfeited (in shares) \| shares	(53)
Ending balance (in shares) \| shares	1,042
Fair Value Assumptions
Share price (CAD per share) \| $ / shares	$ 13.01
Calculated fair value of phantom share units \| $	$ 4,699
Total liability \| $	4,699
Long-term accrued liabilities \| $	528
Current accrued liabilities \| $	$ 4,171
Phantom Share Units \| Minimum
Fair Value Assumptions
Remaining life of phantom share units	10 months 9 days
Phantom Share Units \| Maximum
Fair Value Assumptions
Remaining life of phantom share units	2 years 10 months 9 days

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable after one year (or the operating cycle, if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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

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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.

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Price of a single share of a number of saleable stocks of a company.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 50
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Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Fair Value

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