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OPERATING SEGMENT INFORMATION - Additional Information (Details) € in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 EUR (€) Employees | Jun. 30, 2019 EUR (€) | Jun. 30, 2020 EUR (€) Employees | Jun. 30, 2019 EUR (€)
Disclosure of operating segments [line items] |  |  |  |
Number of employees | Employees | 12,400 |  | 12,400 |
Revenue | € 1,031 | € 1,538 | € 2,468 | € 3,074
P&ARP |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Revenue | 564 | 819 | 1,313 | 1,645
A&T |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Revenue | 247 | 372 | 596 | 739
AS&I |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Revenue | € 220 | € 347 | € 559 | € 690

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