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| r0.c1 | Operating result (used in cash flow statement)/Previous | rj-i:OperatingResultCashFlow | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r1.c0 | Adjustments for depreciation and amortisation expense/Current | rj-i:AdjustmentsDepreciationAndAmortisationExpense | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r1.c1 | Adjustments for depreciation and amortisation expense/Previous | rj-i:AdjustmentsDepreciationAndAmortisationExpense | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r2.c0 | Adjustments for (reversal of) impairment recognised in profit or loss/Current | kvk-i:AdjustmentsImpairmentLossReversalImpairmentLossRecognisedInProfitLoss | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r2.c1 | Adjustments for (reversal of) impairment recognised in profit or loss/Previous | kvk-i:AdjustmentsImpairmentLossReversalImpairmentLossRecognisedInProfitLoss | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r3.c0 | Increase (decrease) in provisions/Current | rj-i:IncreaseDecreaseProvisions | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r3.c1 | Increase (decrease) in provisions/Previous | rj-i:IncreaseDecreaseProvisions | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r4.c0 | Other adjustments to reconcile to the operating result/Current | kvk-i:AdjustmentsReconcileOperatingResultOther | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r4.c1 | Other adjustments to reconcile to the operating result/Previous | kvk-i:AdjustmentsReconcileOperatingResultOther | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r5.c0 | Adjustments to reconcile to the operating result/Current | rj-i:AdjustmentsReconcileOperatingResult | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r5.c1 | Adjustments to reconcile to the operating result/Previous | rj-i:AdjustmentsReconcileOperatingResult | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r6.c0 | Adjustments to reconcile to the operating result [title]/Current | ocw-abstr:AdjustmentsReconcileOperatingResultTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r6.c1 | Adjustments to reconcile to the operating result [title]/Previous | ocw-abstr:AdjustmentsReconcileOperatingResultTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r7.c0 | Decrease (increase) in inventories/Current | rj-i:IncreaseDecreaseInInventories | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r7.c1 | Decrease (increase) in inventories/Previous | rj-i:IncreaseDecreaseInInventories | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r8.c0 | Adjustments for decrease (increase) in current receivables/Current | ocw-i:AdjustmentsDecreaseIncreaseReceivablesCurrent | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r8.c1 | Adjustments for decrease (increase) in current receivables/Previous | ocw-i:AdjustmentsDecreaseIncreaseReceivablesCurrent | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r9.c0 | Decrease (increase) in securities/Current | kvk-i:IncreaseDecreaseInSecurities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r9.c1 | Decrease (increase) in securities/Previous | kvk-i:IncreaseDecreaseInSecurities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r10.c0 | Adjustments for increase (decrease) in current liabilities/Current | ocw-i:AdjustmentsIncreaseDecreaseLiabilitiesCurrent | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r10.c1 | Adjustments for increase (decrease) in current liabilities/Previous | ocw-i:AdjustmentsIncreaseDecreaseLiabilitiesCurrent | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r11.c0 | Changes in working capital/Current | rj-i:ChangesWorkingCapital | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r11.c1 | Changes in working capital/Previous | rj-i:ChangesWorkingCapital | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r12.c0 | Increase (decrease) in working capital [title]/Current | ocw-abstr:AdjustmentsIncreaseDecreaseInWorkingCapitalTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r12.c1 | Increase (decrease) in working capital [title]/Previous | ocw-abstr:AdjustmentsIncreaseDecreaseInWorkingCapitalTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r13.c0 | Cash flows from (used in) operations/Current | rj-i:CashFlowFromOperations | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r13.c1 | Cash flows from (used in) operations/Previous | rj-i:CashFlowFromOperations | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r14.c0 | Interest received (from operating activities)/Current | rj-i:InterestReceivedClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r14.c1 | Interest received (from operating activities)/Previous | rj-i:InterestReceivedClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r15.c0 | Interest paid (from operating activities)/Current | rj-i:InterestPaidClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r15.c1 | Interest paid (from operating activities)/Previous | rj-i:InterestPaidClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r16.c0 | Dividends received (from operating activities)/Current | rj-i:DividendsReceivedClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r16.c1 | Dividends received (from operating activities)/Previous | rj-i:DividendsReceivedClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r17.c0 | Cashflow from other financial assets/Current | ocw-i:CashFlowFromOtherFinancialAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r17.c1 | Cashflow from other financial assets/Previous | ocw-i:CashFlowFromOtherFinancialAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r18.c0 | Income tax paid (from operating activities)/Current | rj-i:IncomeTaxPaidClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r18.c1 | Income tax paid (from operating activities)/Previous | rj-i:IncomeTaxPaidClassifiedAsOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r19.c0 | Cash flows from (used in) operating activities/Current | rj-i:CashFlowOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r19.c1 | Cash flows from (used in) operating activities/Previous | rj-i:CashFlowOperatingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r20.c0 | Cash flows from (used in) operating activities [title]/Current | ocw-abstr:CashFlowOperatingActivitiesTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r20.c1 | Cash flows from (used in) operating activities [title]/Previous | ocw-abstr:CashFlowOperatingActivitiesTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r21.c0 | Purchase of intangible assets/Current | rj-i:PurchaseIntangibleAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r21.c1 | Purchase of intangible assets/Previous | rj-i:PurchaseIntangibleAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r22.c0 | Proceeds from sales of intangible assets/Current | rj-i:ProceedsSalesIntangibleAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r22.c1 | Proceeds from sales of intangible assets/Previous | rj-i:ProceedsSalesIntangibleAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r23.c0 | Purchase of property, plant and equipment/Current | rj-i:PurchasePropertyPlantEquipment | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r23.c1 | Purchase of property, plant and equipment/Previous | rj-i:PurchasePropertyPlantEquipment | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r24.c0 | Proceeds from sales of property, plant and equipment/Current | rj-i:ProceedsSalesPropertyPlantAndEquipment | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r24.c1 | Proceeds from sales of property, plant and equipment/Previous | rj-i:ProceedsSalesPropertyPlantAndEquipment | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r25.c0 | Investments in participations and joint ventures/Current | ocw-i:AdjustmentsIncreaseDecreaseInParticipatonsJointVentures | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r25.c1 | Investments in participations and joint ventures/Previous | ocw-i:AdjustmentsIncreaseDecreaseInParticipatonsJointVentures | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r26.c0 | Increase (decrease) in receivables from OCW and EZ/Current | ocw-i:AdjustmentsIncreaseDecreaseInReceivablesOCWAndEZ | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r26.c1 | Increase (decrease) in receivables from OCW and EZ/Previous | ocw-i:AdjustmentsIncreaseDecreaseInReceivablesOCWAndEZ | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r27.c0 | Increase (decrease) in other financial assets/Current | ocw-i:AdjustmentsIncreaseDecreaseInOtherFinancialAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r27.c1 | Increase (decrease) in other financial assets/Previous | ocw-i:AdjustmentsIncreaseDecreaseInOtherFinancialAssets | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r28.c0 | Cash flows from (used in) investing activities/Current | rj-i:CashFlowInvestingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r28.c1 | Cash flows from (used in) investing activities/Previous | rj-i:CashFlowInvestingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r29.c0 | Cash flows from (used in) investment activities [title]/Current | ocw-abstr:CashFlowInvestingActivitiesTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r29.c1 | Cash flows from (used in) investment activities [title]/Previous | ocw-abstr:CashFlowInvestingActivitiesTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r30.c0 | Proceeds from borrowings/Current | rj-i:ProceedsFromBorrowings | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r30.c1 | Proceeds from borrowings/Previous | rj-i:ProceedsFromBorrowings | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r31.c0 | Repayments of borrowings/Current | rj-i:RepaymentsBorrowings | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r31.c1 | Repayments of borrowings/Previous | rj-i:RepaymentsBorrowings | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r32.c0 | Cash flows from (used in) financing activities/Current | rj-i:CashFlowFinancingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r32.c1 | Cash flows from (used in) financing activities/Previous | rj-i:CashFlowFinancingActivities | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r33.c0 | Cash flows from (used in) financing activities [title]/Current | ocw-abstr:CashFlowFinancingActivitiesTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r33.c1 | Cash flows from (used in) financing activities [title]/Previous | ocw-abstr:CashFlowFinancingActivitiesTitle | xbrli:stringItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r34.c0 | Cashflow other/Current | ocw-i:CashFlowsOther | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r34.c1 | Cashflow other/Previous | ocw-i:CashFlowsOther | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |
| r35.c0 | Increase (decrease) in cash and cash equivalents/Current | rj-i:IncreaseDecreaseCashAndCashEquivalents | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2017-01-01')/xs:date('2017-12-31') | venj-bw2-dm:SeparateMember |
| r35.c1 | Increase (decrease) in cash and cash equivalents/Previous | rj-i:IncreaseDecreaseCashAndCashEquivalents | nl-types:monetaryNoDecimalsItemType | duration | ocw-dm:ActualsMember | xs:date('2016-01-01')/xs:date('2016-12-31') | venj-bw2-dm:SeparateMember |