v3.5.0.2

Equity compensation plans (Details) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Jan. 22, 2015 CAD / shares	Sep. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2015 USD ($)
Units
Outstanding at the beginning of the period (in shares)				1,298,401
Granted (in shares)				1,594,954
Vested and redeemed (in shares)				(771,437)
Forfeitures (in shares)				(7,431)
Outstanding at the end of the period (in shares)		2,114,487		2,114,487
Weighted-Average Fair Value per Unit
Outstanding at the beginning of the period (in dollars per share) | $ / shares				$ 2.88
Granted (in dollars per share) | $ / shares				1.81
Vested and redeemed (in dollars per share) | $ / shares				2.85
Forfeitures (in dollars per share) | $ / shares				2.71
Outstanding at the end of the period (in dollars per share) | $ / shares		$ 1.84		$ 1.84
Long-term incentive plan
Weighted-Average Fair Value per Unit
Cash payments made for vested notional units | $				$ 0.4	$ 1.0
Compensation expense related to LTIP | $		$ 0.5	$ 1.0	$ 1.4	$ 2.1
Transition equity participation agreement
Transition equity participation agreement
Number of transition notional shares outstanding				539,904
Vesting percentage				50.00%
Vesting period				4 years
Period after which remaining portions vests				2 years
Market price (in dollars per share) | CAD / shares	CAD 3.18
Minimum market price required for 3 consecutive months to vest remaining shares | CAD / shares	CAD 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
Minimum percentage by which weighted average Canadian dollar price exceeds market price	50.00%

X

- 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.

+ References

No definition available.

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Represents the minimum percentage by which weighted average Canadian dollar price of common share exceeds the market price of common share.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Represents the period after which the remaining portion of the shares granted vest upon the employee.

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

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).

+ References

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (c)(2)(i)-(ii)
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- Definition

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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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

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

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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