| De bruto waarde van de goodwill. | nl | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Bruttofirmenwert | de | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Gross value of goodwill | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Valeur brute du goodwill | fr | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Bruto waarde van goodwill | nl | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Bruttowert am Ende der Periode | de | http://www.xbrl.org/2003/role/periodEndLabel | http://www.xbrl.org/2003/role/link |
| Gross value at the end of the period | en | http://www.xbrl.org/2003/role/periodEndLabel | http://www.xbrl.org/2003/role/link |
| Valeur brute à la fin de l'exercice | fr | http://www.xbrl.org/2003/role/periodEndLabel | http://www.xbrl.org/2003/role/link |
| Bruto waarde aan het einde van de periode | nl | http://www.xbrl.org/2003/role/periodEndLabel | http://www.xbrl.org/2003/role/link |
| Bruttowert zu Beginn der Periode | de | http://www.xbrl.org/2003/role/periodStartLabel | http://www.xbrl.org/2003/role/link |
| Gross value at the beginning of the period | en | http://www.xbrl.org/2003/role/periodStartLabel | http://www.xbrl.org/2003/role/link |
| Valeur brute au début de l'exercice | fr | http://www.xbrl.org/2003/role/periodStartLabel | http://www.xbrl.org/2003/role/link |
| Bruto waarde aan het begin van de periode | nl | http://www.xbrl.org/2003/role/periodStartLabel | http://www.xbrl.org/2003/role/link |
| Bruttowert | de | http://www.xbrl.org/2003/role/terseLabel | http://www.xbrl.org/2003/role/link |
| Gross value | en | http://www.xbrl.org/2003/role/terseLabel | http://www.xbrl.org/2003/role/link |
| Valeur brute | fr | http://www.xbrl.org/2003/role/terseLabel | http://www.xbrl.org/2003/role/link |
| Bruto waarde | nl | http://www.xbrl.org/2003/role/terseLabel | http://www.xbrl.org/2003/role/link |