Revenue recognition - Revenue components (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue recognition
Revenue from sale of products and licensing	€ 14,003	€ 14,216	€ 14,543
Revenue from services	7,980	8,150	8,166
Contract revenue recognized under percentage of completion accounting	580	781	932
Total revenue	€ 22,563	€ 23,147	€ 23,641

No definition available.

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- Definition

The amount of revenue arising from construction contracts. Construction contracts are contracts specifically negotiated for the construction of an asset or a combination of assets that are closely interrelated or interdependent in terms of their design, technology and function or their ultimate purpose or use. [Refer: Revenue]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

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. [Refer: Revenue]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of revenue arising from the rendering of services. [Refer: Revenue]

+ References

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- Definition

The amount of revenue arising from the sale of goods. [Refer: Revenue]

+ References

+ Details

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