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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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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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The number of personnel employed by the entity at a date.

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The amount of revenue from contracts with customers. A customer is a party that has contracted with an entity to obtain goods or services that are an output of the entity’s ordinary activities in exchange for consideration.

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