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Provisions - Employee obligations - North America plan assets (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
North America |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | $ 71,820 |
Obligations at end of year | $ 64,832 | $ 71,820
Disclosure of fair value of plan assets [abstract] |  |
Cash | 1.00% | 2.00%
Equity mutual funds | 40.00% | 45.00%
Fixed income securities | 59.00% | 51.00%
Real estate mutual funds |  | 2.00%
Total | 100.00% | 100.00%
Ifrs Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at the beginning of the year | $ 52,152 |
Fair value of plan assets at the end of the year | 46,114 | $ 52,152
North America | Pension Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 62,983 |
Obligations at end of year | 57,455 | 62,983
North America | Post Retirement Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 8,837 |
Obligations at end of year | 7,377 | 8,837
USA | Pension Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 38,195 |
Obligations at end of year | 35,062 | 38,195
Ifrs Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at the beginning of the year | 32,869 |
Fair value of plan assets at the end of the year | 29,038 | 32,869
CANADA | Pension Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 24,788 |
Obligations at end of year | 22,393 | 24,788
Ifrs Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at the beginning of the year | 19,283 |
Fair value of plan assets at the end of the year | 17,076 | 19,283
CANADA | Post Retirement Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 8,837 |
Obligations at end of year | 7,377 | 8,837
Present value of defined benefit obligation [member] | North America |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 71,820 |
Service cost | 642 |
Borrowing costs | 2,413 |
Actuarial differences | (4,505) |
Benefits paid | (3,013) |
Exchange differences | (2,630) |
Plan amendments | 175 |
Expenses | (70) |
Obligations at end of year | 64,832 | 71,820
Present value of defined benefit obligation [member] | USA | Pension Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 38,195 |
Service cost | 185 |
Borrowing costs | 1,300 |
Actuarial differences | (2,849) |
Benefits paid | (1,874) |
Plan amendments | 175 |
Expenses | (70) |
Obligations at end of year | 35,062 | 38,195
Present value of defined benefit obligation [member] | CANADA | Pension Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 24,788 |
Service cost | 123 |
Borrowing costs | 816 |
Actuarial differences | (416) |
Benefits paid | (978) |
Exchange differences | (1,940) |
Obligations at end of year | 22,393 | 24,788
Present value of defined benefit obligation [member] | CANADA | Post Retirement Plans |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 8,837 |
Service cost | 334 |
Borrowing costs | 297 |
Actuarial differences | (1,240) |
Benefits paid | (161) |
Exchange differences | (690) |
Obligations at end of year | 7,377 | 8,837
Plan assets [member] | North America |  |
Ifrs Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at the beginning of the year | 52,152 |
Interest income on assets | 1,753 |
Benefits paid | (2,852) |
Actuarial return (loss) on plan assets | (4,198) |
Other | (741) |
Fair value of plan assets at the end of the year | 46,114 | 52,152
Plan assets [member] | USA |  |
Ifrs Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at the beginning of the year | 32,869 |
Interest income on assets | 1,110 |
Benefits paid | (1,874) |
Actuarial return (loss) on plan assets | (3,044) |
Other | (23) |
Fair value of plan assets at the end of the year | 29,038 | 32,869
Plan assets [member] | CANADA |  |
Ifrs Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at the beginning of the year | 19,283 |
Interest income on assets | 643 |
Benefits paid | (978) |
Actuarial return (loss) on plan assets | (1,154) |
Other | (718) |
Fair value of plan assets at the end of the year | $ 17,076 | $ 19,283

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- Definition The amount that cash and cash equivalents constitute of the fair value of defined benefit plan assets as a percent of total defined benefit plan assets. + References No definition available. + Details
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- Definition The decrease in the net defined benefit liability (asset) resulting from expenses charged. + References No definition available. + Details
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- Definition The amount that equity mutual funds constitute of the fair value of defined benefit plan assets as a percent of total defined benefit plan assets. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition The amount that real estate mutual funds constitute of the fair value of defined benefit plan assets as a percent of total defined benefit plan assets. + References No definition available. + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from changes in foreign exchange rates. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_e&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_b&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 140 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_140_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_g&doctype=Standard -URIDate 2018-03-16 + Details
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