v3.20.1

Equity compensation plans (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2019 USD ($)	Mar. 31, 2020 $ / shares
Units
Outstanding at the beginning of the period (in shares) | shares	3,578,092
Granted (in shares) | shares	1,866,748
Vested and redeemed (in shares) | shares	(1,702,571)
Forfeitures (in shares) | shares	(23,388)
Outstanding at the end of the period (in shares) | shares	3,718,881
Weighted-Average Fair Value per Unit
Outstanding at the beginning of the period (in dollars per share) | $ / shares	$ 2.38
Granted (in dollars per share) | $ / shares	2.49
Vested and redeemed (in dollars per share) | $ / shares	2.34
Forfeitures (in dollars per share) | $ / shares	2.40
Outstanding at the end of the period (in dollars per share) | $ / shares	$ 2.45
Long-term incentive plan
Weighted-Average Fair Value per Unit
Cash payments made for vested notional units | $	$ 3.3	$ 0.0
Compensation expense related to LTIP | $	$ 1.0	$ 1.4
Transition equity participation agreement
Transition equity participation agreement
Number of transition notional shares outstanding | shares	269,952
Minimum market price required for 3 consecutive months to vest remaining shares | $ / shares			$ 4.77
Transition equity participation agreement | Minimum
Transition equity participation agreement
Number of consecutive months, weighted average Canadian dollar price must exceed market price of share by 50% for vesting	3 months

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- Definition

Represents the Canadian dollar price that must be achieved on TSX for at least 3 consecutive calendar months in order for the remaining shares under transition equity participation agreement to vest.

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Represents the number of consecutive calendar months when weighted average Canadian dollar closing price of common shares must exceed market price per common share by at least 50% before the 50% portion of the transition equity participation agreement may vest.

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The number of notional shares outstanding under the Transition Equity Participation Agreement, not yet vested.

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

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The weighted average fair value as of grant date pertaining to an equity-based plan other than a stock (or unit) option plan which became vested and were redeemed, 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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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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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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- 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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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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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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