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COMMITMENTS - Non-cancellable Lease Commitments Not Capitalized (Details) - EUR (€) € in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Disclosure of non-cancellable operating leases commitments [line items] |  |
Non-cancellable operating lease minimum payments | € 22 | € 16
Less than 1 year |  |
Disclosure of non-cancellable operating leases commitments [line items] |  |
Non-cancellable operating lease minimum payments | 6 | 5
1 to 5 years |  |
Disclosure of non-cancellable operating leases commitments [line items] |  |
Non-cancellable operating lease minimum payments | 11 | 10
More than 5 years |  |
Disclosure of non-cancellable operating leases commitments [line items] |  |
Non-cancellable operating lease minimum payments | € 5 | € 1

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