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SHARE-BASED COMPENSATION - Inputs to the Model Used for PSUs Granted (Details) - PSUs	6 Months Ended
	Jun. 30, 2020 € / shares
Disclosure of Input of Model Used for Performance-Based RSU [Line Items]
Fair value at grant date (in euros)	€ 6.65
Share price at grant date (in euros)	€ 4.64
Dividend yield	0.00%
Expected volatility	63.00%
Risk-free interest rate (US government bond yield)	0.36%

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- Definition

Disclosure of input of model used for performance-based RSU.

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Expected dividend as percentage, other equity instruments granted.

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Risk free interest rate, other equity instruments granted.

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