| r0.c0 | Disclosure of current assets/Current | venj-bw2-i:AssetsCurrentDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r1.c0 | Disclosure of inventories/Current | venj-bw2-i:InventoriesDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r2.c0 | Disclosure of inventory raw materials and consumables/Current | venj-bw2-i:InventoryRawMaterialsConsumablesDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r3.c0 | Disclosure of prepayments of inventories/Current | venj-bw2-i:PrepaymentsInventoriesDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r4.c0 | Inventories [title]/Current | kvk-abstr:InventoriesDisclosureTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r5.c0 | Disclosure of receivables/Current | venj-bw2-i:ReceivablesDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r6.c0 | Disclosure of trade receivables/Current | venj-bw2-i:TradeReceivablesDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r7.c0 | Disclosure of receivables from OCW and EZ (current)/Current | ocw-i:ReceivablesOCWAndEZCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r8.c0 | Disclosure of receivables from local government and common regulations (current)/Current | ocw-i:ReceivablesLocalGovernmentCommonRegulationsCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r9.c0 | Disclosure of current receivables from group companies/Current | venj-bw2-i:ReceivablesGroupCompaniesCurrentDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r10.c0 | Disclosure of receivables from other participating interests (current)/Current | ocw-i:ReceivablesOtherParticipatingInterestsCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r11.c0 | Disclosure of receivables from personnel (current)/Current | ocw-i:ReceivablesEmployeesCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r12.c0 | Disclosure of receivables from parents, students and course participants (current)/Current | ocw-i:ReceivablesParentsStudentsAndCourseParticipantsCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r13.c0 | Disclosure of receivables from other government institutions (current)/Current | ocw-i:ReceivablesGovernmentOtherCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r14.c0 | Disclosure of construction contracts/Current | rj-i:ConstructionContractsDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r15.c0 | Disclosure of current other receivables/Current | venj-bw2-i:ReceivablesOtherCurrentDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r16.c0 | Disclosure of receivables, provision bad debts/Current | ocw-i:ReceivablesProvisionBadDebtsDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r17.c0 | Disclosure of receivables current excluding accrued income, subtotal/Current | ocw-i:ReceivablesCurrentExcludingAccruedIncomeSubtotalDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r18.c0 | Disclosure of prepayments and accrued income/Current | venj-bw2-i:AccruedIncomeDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r19.c0 | Disclosure of receivables from taxes and social security contributions (current)/Current | ocw-i:TaxesSocialSecurityContributionsReceivableCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r20.c0 | Disclosure of prepayments/Current | ocw-i:AdvancesPaidPrepaymentsDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r21.c0 | Disclosure of periodic payments/Current | ocw-i:AdvancesPaidPeriodicPaymentsDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r22.c0 | Disclosure of interest receivable/Current | ocw-i:InterestReceivableDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r23.c0 | Disclosure of other accrued income/Current | venj-bw2-i:AccruedIncomeOtherDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r24.c0 | Disclosure of accrued income [title]/Current | kvk-abstr:AccruedIncomeDisclosureTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r25.c0 | Receivables [title]/Current | kvk-abstr:ReceivablesDisclosureTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r26.c0 | Disclosure of current securities/Current | venj-bw2-i:SecuritiesCurrentDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r27.c0 | Disclosure of current shares and other variable-yield securities/Current | ocw-i:SharesOtherVariableYieldSecuritiesCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r28.c0 | Disclosure of current bonds and other fixed-income securities/Current | ocw-i:BondsOtherFixedIncomeSecuritiesCurrentDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r29.c0 | Securities [title]/Current | kvk-abstr:SecuritiesDisclosureTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r30.c0 | Disclosure of cash and cash equivalents/Current | venj-bw2-i:CashAndCashEquivalentsDisclosure | nl-types:formattedExplanationItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r31.c0 | Disclosure of cash/Current | ocw-i:CashDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r32.c0 | Disclosure of bank accounts balance/Current | ocw-i:BankAccountsBalanceDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r33.c0 | Disclosure of deposits/Current | ocw-i:DepositsDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r34.c0 | Disclosure of treasury banking/Current | ocw-i:TreasuryBankingDisclosure | nl-types:string100000ItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r35.c0 | Cash and cash equivalents [title]/Current | kvk-abstr:CashAndCashEquivalentsDisclosureTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |