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The number of equity compensation plans during the period.

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The number of units expected to vest on an annual basis under the plan.

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Number Of Units Vesting Immediately

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Number of equal installments in which non-performance award vests.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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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 number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The highest quantity of shares an employee can purchase under the plan per period.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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

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-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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options outstanding, including both vested and non-vested options.

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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SHAREHOLDERS' EQUITY - Narrative (Details) $ in Millions	1 Months Ended				2 Months Ended	3 Months Ended	12 Months Ended
SHAREHOLDERS' EQUITY - Narrative (Details) $ in Millions	Feb. 29, 2016 Installment shares	Jul. 31, 2015 Installment shares	Nov. 30, 2011 Installment shares	Aug. 31, 2010 Installment shares	Nov. 30, 2017 Installment shares	Mar. 31, 2012 Installment shares	Dec. 31, 2017 USD ($) plan director shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Oct. 31, 2017 Installment shares	Dec. 31, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of compensation plans \| plan							3
Share based compensation cost \| $							$ 1.6	$ 1.7	$ 0.9
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised \| $							$ 1.3	$ 0.0	$ 0.0
Number of options outstanding (in shares)							1,001,300	1,410,250	954,625		1,127,250
Share based compensation cost \| $							$ 1.1	$ 0.8	$ 0.2
Share based compensation cost, future income tax benefits \| $							0.2	0.3	0.1
Unrecognized compensation costs, unvested stock options \| $							$ 1.0
Weighted average period of recognition							2 years 5 months 19 days
Total fair value of stock options vested \| $							$ 0.9	0.6	1.1
Employee Stock Option \| ETG
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $							0.0	0.1	0.0
Restricted Stock Units (RSUs) \| Key Employee \| Granted November 2011 \| Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $							0.1	0.1	0.2
Restricted Stock Units (RSUs) \| Key Employee \| Grant February 2016 \| Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $							0.2	0.5
Restricted Stock Units (RSUs) \| Two Key Employees \| Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $							0.1	0.1	0.4
Restricted Stock Units (RSUs) \| Director \| Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $							$ (0.1)	0.1	0.1
1999 Long-term Stock Incentive Plan, as amended
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)							7,500,000
Number of shares granted per calendar year in total, maximum (in shares)							3,000,000
1999 Long-term Stock Incentive Plan, as amended \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted per calendar year in total, maximum (in shares)							1,500,000
Number of options outstanding (in shares)							158,375
2006 Stock Incentive Plan For Non-Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)							200,000
2006 Stock Incentive Plan For Non-Employee Directors \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)							5,000
2010 Long-term Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)							7,500,000
2010 Long-term Stock Incentive Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted per calendar year in total, maximum (in shares)							1,500,000
Number of options outstanding (in shares)							837,925
2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding (in shares)							191,267
2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs) \| Key Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of directors that resigned during period \| director							2,000,000
Share based compensation cost \| $							$ 0.1		0.1
Restricted Stock and Restricted Stock Units [Abstract]
RSU's granted (in shares)	100,000	23,620	100,000		53,288
Number of vesting installments \| Installment	3	4	10		3					2
Number of units vesting immediately										1,844
Number of units vesting annually (in shares)		5,905	10,000		49,600
2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs) \| Key Employee \| Granted August 2010
Restricted Stock and Restricted Stock Units [Abstract]
RSU's granted (in shares)				175,000
Number of vesting installments \| Installment				10
Number of units vesting annually (in shares)				17,500
2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs) \| Key Employee \| Granted August 2010 \| Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $							$ 0.1	$ 0.1	$ 0.2
2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs) \| Two Key Employees
Restricted Stock and Restricted Stock Units [Abstract]
RSU's granted (in shares)						50,000
Number of vesting installments \| Installment						10
Number of units vesting annually (in shares)						10,000
RSU's vested (in shares)						35,000