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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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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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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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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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SHAREHOLDERS' EQUITY - Narrative (Details) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended	12 Months Ended
	Dec. 31, 2018 shares	Jul. 31, 2018 shares	Mar. 31, 2019 USD ($) shares	Dec. 31, 2019 USD ($) plan $ / shares shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) director shares	Dec. 31, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of compensation plans \| plan				1
Share based compensation cost				$ 5.4	$ 0.9	$ 1.6
Number of options repriced (shares) \| shares			600,000
Restricted Stock and Restricted Stock Units [Abstract]
Share repurchased (in shares) \| shares		232,550			232,550
Shares repurchased, value				$ 0.0	$ 9.1	$ 0.0
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares) \| shares	596,148			764,784	596,148	1,001,300	1,410,250
Share based compensation cost				$ 3.3	$ 0.3	$ 1.1
Share based compensation cost, future income tax benefits				0.7	0.1	0.2
Total intrinsic value of options exercised				3.4	9.5	1.3
Unrecognized compensation costs, unvested stock options				$ 2.5
Weighted average period of recognition (years)				3 years 8 months 19 days
Total fair value of stock options vested				$ 4.0	1.2	0.9
Restricted Stock and Restricted Stock Units [Abstract]
Compensation Expense			$ 0.6	$ 0.7
Employee Stock Option \| ETG
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost					0.4
Acceleration of stock options due to sale of business					0.3
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period of recognition (years)				3 years 18 days
Restricted Stock and Restricted Stock Units [Abstract]
Unrecognized compensation cost				$ 2.5
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				$ 0.2	$ 0.1	$ (0.1)
2010 Long-term Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period (years)				10 years
Number of shares authorized for issuance (in shares) \| 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) \| shares				1,500,000
Number of options outstanding (in shares) \| shares				764,784
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) \| shares				172,595
2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs) \| Key Employee
Restricted Stock and Restricted Stock Units [Abstract]
Number of directors that resigned during period \| director						2
2018 Employee Stock Purchase Plan \| Employee Stock
Restricted Stock and Restricted Stock Units [Abstract]
Shares reserved for issuance (in shares) \| shares	500,000			455,771	500,000
Stock plan offering period (months)	6 months
Employee stock purchase plan, maximum shares available to purchase (in shares) \| shares	10,000
Employee stock purchase plan, purchase price of stock, percent	85.00%
Stock issued during period under ESPP (in shares) \| shares				44,229
Average purchase price of shares issues under ESPP (USD per share) \| $ / shares				$ 17.61
2018 Employee Stock Purchase Plan \| Employee Stock \| Selling, General and Administrative Expenses
Restricted Stock and Restricted Stock Units [Abstract]
Compensation Expense				$ 0.3	$ 0.1
Discontinued Operations \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost					1.5
Discontinued Operations \| 2010 Long-term Stock Incentive Plan \| Restricted Stock Units (RSUs) \| Key Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost						$ 0.1
Continuing Operations \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost				$ 1.8	$ 0.5	$ 0.5