The percentage of shares issuable under stock option plan to the total number of shares issued and outstanding.

No definition available.

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- Definition

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

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- Definition

Description of why the actual reporting currency-denominated balances differ from the amounts reported for financial reporting purposes, including the reasons for using two different rates with respect to remeasurement and translation. For example, in certain jurisdictions, companies may utilize an official exchange rate and also a parallel rate.

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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

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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-Publisher FASB
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Description of modification of award under share-based payment arrangement. Includes, but is not limited to, terms for expiration date, vesting rights and exercise price.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Amount of noncash expense for option under share-based payment arrangement.

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Stock options - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions		12 Months Ended
	Jun. 24, 2010	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense		$ 100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		9,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value		$ 2,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Description and Terms			the Company modified the terms of certain options granted to executives and directors by extending the expiration date by a weighted average amount of 2.0 years.
Description of Difference between Reported Amount and Reporting Currency Denominated Amount			exchange rate of $CAD/$USD 0.7715
Weighted Average Remaining Life (years)		2 years 11 months 23 days
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense		$ 3,100,000	$ 2,100,000
Stock or Unit Option Plan Expense		$ 1,340,000	$ 112,000
Plan Maximum Amendment [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under Stock Option Plan	5.0
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under Stock Option Plan	6.7
Percentage Of Total Number Of Share Issued and Outstanding	25.00%	25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 4.83	$ 9.12