v3.10.0.1
Commitments and Contingencies - Additional Information (Details)
€ in Millions
12 Months Ended
Dec. 31, 2018
EUR (€)
Lawsuit
Dec. 31, 2017
EUR (€)
Dec. 31, 2016
EUR (€)
Commitments And Contingencies [Line Items]      
Lease expenses € 79 € 52 € 19
Number of lawsuits on alleging unlawful practices | Lawsuit 6    
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Commitments And Contingencies [Line Items]      
Minimum Spend Commitments Under Service Agreement € 270    
Service Agreement Term 2 years