v3.20.1

Financial risk management - Interest rate risk and foreign exchange risk (Details) - EUR (€) € in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Interest rate risk |  |  |
Financial risk management |  |  |
Increase in interest rates | 1.00% | 1.00% | 1.00%
Decrease in interest rates | 1.00% | 1.00% | 1.00%
Approximate increase in profit or loss, and equity from increase in interest rates | € 57,800 | € 12,900 | € 11,500
Approximate decrease in profit or loss, and equity from decrease in interest rates | € 57,800 | € 12,900 | € 11,500
Foreign exchange risk |  |  |
Financial risk management |  |  |
Percentage of change in risk assumption | 10.00% | 10.00% | 10.00%
Euros - U.S. Dollars Exchange rate value | Foreign exchange risk |  |  |
Financial risk management |  |  |
Increase (Decrease) in net book value | € (133,373) | € (27,200) | € (21,083)
Euros - GB Pounds Exchange rate value | Foreign exchange risk |  |  |
Financial risk management |  |  |
Increase (Decrease) in net book value | 113 | 100 | 122
Euros - CH Francs Exchange rate value | Foreign exchange risk |  |  |
Financial risk management |  |  |
Increase (Decrease) in net book value | 538 | 208 | 203
Euros - HR Kunas Exchange rate value | Foreign exchange risk |  |  |
Financial risk management |  |  |
Increase (Decrease) in net book value | 650 | 611 | (185)
U.S. Dollars - GB Pounds Exchange rate value | Foreign exchange risk |  |  |
Financial risk management |  |  |
Increase (Decrease) in net book value | € (894) | € (923) | € (831)

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