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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Amount of noncash expense for share-based payment arrangement.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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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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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	Mar. 31, 2019 shares	Dec. 31, 2020 USD ($) plan $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of compensation plans \| plan			2
Share based compensation cost \| $			$ 4.7	$ 5.4	$ 0.9
Compensation Expense \| $					$ 0.1
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares) \| shares	596,148		661,024	764,784	596,148	1,001,300
Share based compensation cost \| $			$ 1.8	$ 3.3	$ 0.3
Number of options repriced (shares) \| shares		600,000
Share based compensation cost, future income tax benefits \| $			0.4	0.7	0.1
Total intrinsic value of options exercised \| $			3.9	3.4	9.5
Unrecognized compensation costs, unvested stock options \| $			$ 1.6
Weighted average period of recognition (years)			3 years 4 months 9 days
Total fair value of stock options vested \| $			$ 2.5	4.0	1.2
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)			2 years 5 months 19 days
Unrecognized compensation cost \| $			$ 1.7
Restricted Stock Units (RSUs) \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding (in shares) \| shares			17,600
Restricted Stock Units (RSUs) \| Director \| Selling, Distribution and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $			$ 0.2	0.2	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 \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding (in shares) \| shares			7,356
2010 Long-term Stock Incentive Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares) \| shares			661,024
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			153,516
2010 Long-term Stock Incentive Plan \| Stock Option and Restricted Stock Units
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
2020 Omnibus Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period (years)			10 years
Cash performance awards \| $			$ 10.0
Number of shares authorized for issuance (in shares) \| shares			7,500,000
2020 Omnibus Stock Incentive Plan \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding (in shares) \| shares			10,244
2020 Omnibus 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
2020 Omnibus Stock Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding (in shares) \| shares			10,244
2018 Employee Stock Purchase Plan \| Employee Stock Option \| Selling, Distribution and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation Expense \| $			$ 0.3	$ 0.3	$ 0.1
2018 Employee Stock Purchase Plan \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares) \| shares	500,000		406,144		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			49,627	44,229
Average purchase price of shares issues under ESPP (USD per share) \| $ / shares			$ 16.85	$ 17.61
Continuing Operations \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost \| $			$ 2.5	$ 1.8	$ 0.5