Pension and other post-retirement benefits - Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status (Detail) - CAD CAD in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Pension Plans
Change in projected benefit obligation
Projected benefit obligation, beginning of year	CAD 241,963	CAD 178,113
Projected benefit obligation assumed from business combination	0	1,022
Modifications to pension plan	(4,995)	(560)
Service cost	6,663	4,828
Interest cost	9,642	8,549
Actuarial loss (gain)	(16,098)	39,704
Contributions from retirees	0	0
Benefits paid	(13,024)	(8,125)
Loss on foreign exchange	45,231	18,432
Projected benefit obligation, at end of year	269,382	241,963
Change in plan assets
Fair value of plan assets, beginning of year	156,990	139,280
Actual return (loss) on plan assets	(5,657)	6,568
Employer contributions	7,975	5,676
Benefits paid	(12,589)	(7,414)
Gain on foreign exchange	29,453	12,880
Fair value of plan assets, end of year	176,172	156,990
Unfunded status	(93,210)	(84,973)
Current liabilities	(470)	0
Non-current liabilities	(92,740)	(84,973)
Net amount recognized	(93,210)	(84,973)
Other Postretirement Benefit Plans, Defined Benefit
Change in projected benefit obligation
Projected benefit obligation, beginning of year	68,257	45,399
Projected benefit obligation assumed from business combination	0	0
Modifications to pension plan	0	0
Service cost	3,093	2,022
Interest cost	2,914	2,186
Actuarial loss (gain)	(8,466)	14,893
Contributions from retirees	412	331
Benefits paid	(2,447)	(1,586)
Loss on foreign exchange	12,802	5,012
Projected benefit obligation, at end of year	76,565	68,257
Change in plan assets
Fair value of plan assets, beginning of year	14,295	13,395
Actual return (loss) on plan assets	20	1,176
Employer contributions	3,028	(222)
Benefits paid	(2,036)	(1,255)
Gain on foreign exchange	2,842	1,201
Fair value of plan assets, end of year	18,149	14,295
Unfunded status	(58,416)	(53,962)
Current liabilities	(1,062)	(333)
Non-current liabilities	(57,354)	(53,629)
Net amount recognized	CAD (58,416)	CAD (53,962)

Defined Benefit Plan, Benefits Paid, Plan Assets

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- Definition

This represents the entire liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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This represents the current liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)
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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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- Definition

The amount of increase in the benefit obligation attributed to business combinations.

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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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No definition available.

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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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No definition available.

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The increase in the fair value of plan assets from contributions made by the employer.

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The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency.

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The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

+ References

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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