PENSION, POST-RETIREMENT AND OTHER LONG-TERM EMPLOYEE BENEFIT PLANS - Reconciliation of Defined Benefit Obligations and Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Current service cost	$ 1,237	$ 1,122	$ 1,198
Interest cost (income)	920	1,182	1,317
Administration expenses	(611)	(507)	(487)
Funded status – deficit	14,898	29,298
Pension Plans
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Current service cost	1,193	1,076	1,176
Interest cost (income)	814	1,071	1,174
Actuarial gains from demographic assumptions	(163)	(1,052)	(1,131)
Actuarial losses (gains) from financial assumptions	(5,186)	3,989	1,901
Experience losses (gains)	266	2,077	1,383
Return on plan assets (excluding amounts included in net interest expense)	(2,369)	5,591	1,705
Administration expenses	(611)	(507)	(487)
Funded status – deficit	12,118	26,146
Pension Plans \| Defined benefit obligations
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Net defined benefit liability (asset)	86,462	79,821
Current service cost	1,193	1,076
Interest cost (income)	3,031	3,096
Benefits paid	(3,701)	(3,406)
Actuarial gains from demographic assumptions	(163)	(1,052)
Actuarial losses (gains) from financial assumptions	(5,186)	3,989
Experience losses (gains)	266	2,077
Foreign exchange rate adjustment	(1,206)	861
Net defined benefit liability (asset)	80,696	86,462	79,821
Pension Plans \| Fair value of plan assets
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Net defined benefit liability (asset)	(60,316)	(51,856)
Interest cost (income)	(2,217)	(2,025)
Benefits paid	3,701	3,406
Foreign exchange rate adjustment	1,079	(801)
Return on plan assets (excluding amounts included in net interest expense)	(2,369)	5,591
Contributions by the employer	13,805	3,956
Administration expenses	(611)	(507)
Net defined benefit liability (asset)	(68,578)	(60,316)	(51,856)
Other Plans
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Current service cost	44	46	22
Interest cost (income)	106	111	143
Actuarial gains from demographic assumptions	21	(565)	(21)
Actuarial losses (gains) from financial assumptions	(210)	133	141
Experience losses (gains)	(113)	707	(835)
Return on plan assets (excluding amounts included in net interest expense)	0	0	0
Administration expenses	0	0	0
Funded status – deficit	2,780	3,152
Other Plans \| Defined benefit obligations
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Net defined benefit liability (asset)	3,152	2,867
Current service cost	44	46
Interest cost (income)	106	111
Benefits paid	(71)	(246)
Actuarial gains from demographic assumptions	21	(565)
Actuarial losses (gains) from financial assumptions	(210)	133
Experience losses (gains)	(113)	707
Foreign exchange rate adjustment	(149)	99
Net defined benefit liability (asset)	2,780	3,152	2,867
Other Plans \| Fair value of plan assets
Reconciliation of changes in net defined benefit liability (assets) [Abstract]
Net defined benefit liability (asset)	0	0
Interest cost (income)	0	0
Benefits paid	0	0
Foreign exchange rate adjustment	0	0
Return on plan assets (excluding amounts included in net interest expense)	0	0
Contributions by the employer	0	0
Administration expenses	0	0
Net defined benefit liability (asset)	$ 0	$ 0	$ 0

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)]

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)]

+ References

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The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)]

+ References

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- Definition

The decrease (increase) in net defined benefit liability (asset) resulting from contributions to a defined benefit plan by the employer. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]]

+ References

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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

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The increase (decrease) in the net defined benefit liability (asset) resulting from changes in foreign exchange rates. [Refer: Net defined benefit liability (asset)]

+ References

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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

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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

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The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)]

+ References

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The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets. The return on plans assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [member]]

+ References

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The present value of the defined benefit obligation, less the fair value of the plan assets (if any). [Refer: Plan assets [member]]

+ References

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Administration Expenses, Net Defined Benefit Liability (Asset)

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Reconciliation Of Changes In Net Defined Benefit Liability (Asset)

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