v3.20.1

Segment information - Major customers (Details) - EUR (€) € in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of major customers [line items] |  |  |
Revenue | € 844,985 | € 288,836 | € 127,087
North America |  |  |
Disclosure of major customers [line items] |  |  |
Revenue | 795,605 | 117,609 | 82,050
Europe |  |  |
Disclosure of major customers [line items] |  |  |
Revenue | 49,018 | 171,113 | € 45,037
Asia Pacific |  |  |
Disclosure of major customers [line items] |  |  |
Revenue | 362 | € 114 |
Gilead | North America |  |  |
Disclosure of major customers [line items] |  |  |
Percentage of entity's revenue |  |  | 80687.00%
Gilead | North America and Europe |  |  |
Disclosure of major customers [line items] |  |  |
Negative catch-up effect on closing date resulting from the decrease in the percentage of completion applied to previously received upfront and milestones | € 245,900 |  |
AbbVie | Europe |  |  |
Disclosure of major customers [line items] |  |  |
Percentage of entity's revenue |  |  | 34049.00%
Les Laboratoires Servier | Europe |  |  |
Disclosure of major customers [line items] |  |  |
Percentage of entity's revenue |  |  | 67.00%
Revenues by major customers |  |  |
Disclosure of major customers [line items] |  |  |
Percentage of entity's revenue |  |  | 114804.00%

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