OTHER INFORMATION BY NATURE - Narrative (Details) € in Thousands	12 Months Ended
Dec. 31, 2019 EUR (€) employee	Dec. 31, 2018 EUR (€) employee	Dec. 31, 2017 EUR (€) employee
Disclosure of detailed information about intangible assets [line items]
Compensation related to product development	€ 385,182	€ 323,936	€ 313,471
Average number of employees \| employee	4,164	3,651	3,336
Depreciation expense	€ 191,482	€ 156,384	€ 143,484
Accumulated depreciation and amortisation [member]
Disclosure of detailed information about intangible assets [line items]
Amortization	€ 160,464	€ 132,364	€ 117,122

The amount of amortisation of intangible assets other than goodwill. [Refer: Depreciation and amortisation expense; Intangible assets other than goodwill]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 38
-IssueDate 2019-01-01
-Paragraph 118
-Subparagraph e
-Clause vi
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=38&code=ifrs-tx-2019-en-r&anchor=para_118_e_vi&doctype=Standard
-URIDate 2019-03-27

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- Definition

The average number of personnel employed by the entity during a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2019-03-27

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- Definition

The amount of depreciation expense. Depreciation is the systematic allocation of depreciable amounts of tangible assets over their useful lives.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2019-01-01
-Paragraph 9
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_9&doctype=Standard
-URIDate 2019-03-27

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