Document And Entity Information nvo_EBPVestedPercentageUponTerminationOfPlan EBP, Vested Percentage Upon Termination of Plan Vested percentage upon termination of plan in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Statistical Measurement [Axis] Note To Financial Statement Details Textual Document Fiscal Period Focus nvo_EBPNoteReceivableFromParticipantSecuredByVestedAccountsPercentage EBP, Note Receivable From Participant Secured By Vested Accounts Percentage Represents note receivable from participant secured by the amount of vested accounts as percentage in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Basis of Accounting [Policy Text Block] Significant Accounting Policies Document Fiscal Year Focus Note 1 - Description of Plan nvo_EmployeeBenefitPlanEmployerBasicContributionFromParticipantCompensationPercentage Employee Benefit Plan, Employer Basic Contribution From Participant Compensation Percentage Employer basic contribution from participant compensation as percentage in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Note 3 - Fair Value Measurements nvo_EmployeeBenefitPlanMinimumParticipantContributionPercentage Employee Benefit Plan, Minimum Participant Contribution Percentage Minimum participant contribution as percentage in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Schedule of Assets Amendment Flag Note 1 - Description of Plan - Vesting Schedule (Details) nvo_EBPParticipantCatchupContributionMinimumAge EBP, Participant Catchup Contribution, Minimum Age Minimum age required to make catchup contribution in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Note 3 - Fair Value Measurements - Assets at Fair Value (Details) us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest EBP, Asset Held for Investment, Party-in-Interest [true false] EBP, Master Trust [Table] Schedule of Assets (Held at End of Year) (Unaudited) (Details) Schedule of Assets (Held at End of Year) (Unaudited) 2 (Details) Interest Minimum [Member] Notes To Financial Statements Notes To Financial Statements [Abstract] dei_DocumentPeriodEndDate Document Period End Date Statistical Measurement [Domain] us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContribution EBP, Change in Net Asset Available for Benefit, Increase from Contribution Maximum [Member] Legal Entity [Axis] nvo_EBPContributionsReceivable EBP, Contributions Receivable Amount of contribution receivable in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Schedule of Asset Held for Investment [Table] us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate EBP, Asset Held for Investment, Participant Loan, Maturity Date Notes receivable from participants EBP, Note Receivable from Participant nvo_EBPVestingPercentageInYearThreeOfService EBP, Vesting Percentage in Year Three of Service The percent vesting in year three of the employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). dei_EntityTaxIdentificationNumber Entity Tax Identification Number nvo_EBPVestingPercentageInYearOneOfService EBP, Vesting Percentage in Year One of Service The percent vesting in year one of the employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Investment, Fair Value and NAV [Text Block] Entity [Domain] Interest income on notes receivable from participants nvo_EBPVestingPercentageInYearTwoOfService EBP, Vesting Percentage in Year Two of Service The percent vesting in year two of the employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Entity Central Index Key Net depreciation in fair value of investments dei_EntityRegistrantName Entity Registrant Name nvo_EBPVestingPercentageInLessThanOneYearOfService Less than 1 The percent vesting in less than one year of the employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). nvo_EBPChangeInNetAssetAvailableForBenefitDecreaseForFeeExpense EBP, Change in Net Asset Available for Benefit, Decrease for Fee Expense Amount of decrease in net asset available for benefit from fee expense incurred by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Entity Current Reporting Status EBP, Description of Plan [Text Block] Mutual Funds Common Stock and Money Market Funds [Member] Represents Mutual Funds Common Stock and Money Market Funds. us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment EBP, Asset Held for Investment EBP, Related Party and Party-in-Interest Transactions [Table] Current Fiscal Year End Date us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterDate EBP, Tax Determination Letter, Date us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution EBP, Asset Held for Investment, Participant Loan, after Deemed Distribution us-gaap-ebp_EbpFairValueInvestmentNavUnfundedCommitment EBP, Fair Value, Investment, NAV, Unfunded Commitment nvo_PolicyTable Fair Value Measured at Net Asset Value Per Share [Member] Entity Shell Company Common Collective Trust [Member] Participant us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution Entity Emerging Growth Company us-gaap-ebp_EbpFairValueInvestmentNavRedemptionOtherRestrictionDescription EBP, Fair Value, Investment, NAV, Redemption Other Restriction, Description nvo_EBPChangeInNetAssetAvailableForBenefitDecreaseForAdvisoryAndManagedServiceExpense EBP, Change in Net Asset Available for Benefit, Decrease for Advisory and Managed Service Expense Amount of decrease in net asset available for benefit from advisory and managed service expense incurred by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Entity Small Business Novo Nordisk AS [Member] Represents Novo Nordisk AS. Investments [Domain] EBP, Employer, Common Stock [Member] Benefits paid to participants Accounting Policies [Abstract] Employer us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContribution nvo_EBPNumberOfServiceHoursRequiredToParticipateInThePlan EBP, Number of Service Hours Required to Participate in the Plan The number of service hours required to participate in the plan. EBP, Risk and Uncertainty [Table] nvo_EBPParticipantCatchupContributionPretaxMaximumAnnualCompensationAmount EBP, Participant Catch-up Contribution, Pretax, Maximum Annual Compensation, Amount The amount of participant catch-up contribution pretax maximum annual contribution. us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment EBP 06-1061602 002 [Member] Represents EBP 06-1061602 002 Valuation Approach and Technique [Domain] us-gaap-ebp_EmployeeBenefitPlanTaxQualificationStatusExtensibleEnumeration EBP, Tax Qualification Status [Extensible Enumeration] Valuation, Market Approach [Member] us-gaap-ebp_EbpPlanName EBP, Plan Name nvo_EBPNoteReceivableFromParticipantLoanTerm EBP, Note Receivable from Participant, Loan Term The loan term of the note receivable from participant. Statement of Stockholders' Equity [Abstract] EBP, Tax Status [Text Block] us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForAdministrativeExpense EBP, Forfeited Nonvested Account, Decrease from Administrative Expense nvo_EBPEmployerAdditionalDiscretionaryContributionPercentage EBP, Employer Additional Discretionary Contribution, Percentage The percentage of employer additional discretionary contribution. us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount EBP, Forfeited Nonvested Account us-gaap-ebp_EmployeeBenefitPlanInvestmentValuationTechniqueExtensibleEnumeration EBP, Investment, Valuation Technique [Extensible Enumeration] us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Current Value Equity Components [Axis] us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValue EBP, Investment, Fair Value Class of Stock [Axis] Equity Component [Domain] us-gaap-ebp_EbpFairValueInvestmentNavRedemptionNoticePeriod EBP, Fair Value, Investment, NAV, Redemption, Notice Period Dividends from Novo Nordisk A/S common stock Fair Value, Inputs, Level 1 [Member] us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease Net (decrease) increase us-gaap-ebp_EbpFairValueInvestmentNavRedemptionRestrictionPeriodInEffect EBP, Fair Value, Investment, NAV, Redemption Restriction, Period in Effect (Day) us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract Deductions us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract Additions us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate EBP, Asset Held for Investment, Participant Loan, Interest Rate us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForEmployerContribution EBP, Forfeited Nonvested Account, Decrease from Employer Contribution EBP, Participant-Directed [Member] us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract Contributions Mutual funds EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Administrative expenses Investment, Identifier [Axis] EBP, Accounting Policy [Table] us-gaap-ebp_EmployeeBenefitPlanReceivableAbstract Contributions receivable Dividend withholding tax receivable EBP, Dividend Withholding Tax Receivable Amount of receivable for employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), classified as dividend withholding tax. EBP, Description of Plan [Table] Statement [Table] EBP, Tax Status [Table] Fair Value Hierarchy and NAV [Domain] us-gaap-ebp_EmployeeBenefitPlanPlanNumber EBP, Plan Number EBP, Risk and Uncertainty [Text Block] Statement of Financial Position [Abstract] us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration EBP, Investment, Current Value, Type [Extensible Enumeration] EBP, Schedule of Vesting [Table Text Block] Tabular disclosure of the vesting schedule in the employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Mutual Fund Fees [Text Block] Disclosure of mutual fund fees. EBP, Participant-Directed and Nonparticipant-Directed Status [Domain] Investment Type [Axis] Mutual Fund [Member] us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage EBP, Employer Contribution, Matching Percentage EBP, Schedule of Asset Held for Investment [Text Block] EBP, Use of Estimate [Policy Text Block] us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount EBP, Schedule of Assets [Text Block] Disclosure of the assets held at the end of the year. us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMinimumBorrowingAmount EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage nvo_EBPTaxStatusWithholdingTaxPaid EBP, Tax Status, Withholding Tax Paid The amount of withholding tax paid for the employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Related Party and Party-in-Interest [Domain] us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration EBP, Investment, Issuer Name [Extensible Enumeration] dei_DocumentType Document Type EBP, Summary of Accounting Policy [Text Block] Document Information [Line Items] EBP, Investment [Policy Text Block] Employer Document Information [Table] Participant Other dividends Amount of increase in net asset available for benefit from other dividend income on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Trustee [Member] Entity Interactive Data Current Statement [Line Items] Fair Value Hierarchy and NAV [Axis] EBP, Related Party and Party-in-Interest [Axis] us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants EBP, Number of Participants us-gaap-ebp_EmployeeBenefitPlanAsset Total assets EBP, Payment to Participant [Policy Text Block] us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationAmount EBP, Participant Contribution, Pretax, Maximum Annual Compensation, Amount us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage EBP, Employer Contribution, Participant Compensation Matched, Percentage Investment, Issuer Name [Domain] us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterObtained EBP, Tax Determination Letter, Obtained [true false] us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease EBP, Change in Net Asset Available for Benefit, Decrease Money Market Funds [Member] EBP, Related Party and Party-in-Interest Transactions [Text Block] us-gaap-ebp_EmployeeBenefitPlanAssetAbstract Assets EBP, Plan Termination [Text Block] us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit Net assets available for pension benefits Net assets available for benefits, beginning of year Net assets available for benefits, end of year EBP, Investment, Fair Value and NAV [Table Text Block] us-gaap_PolicyTextBlockAbstract Accounting Policies EBP, Investment, Fair Value and NAV [Table] us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements Retirement Plan Tax Status [Domain] us-gaap_TableTextBlock Notes Tables Qualified Plan [Member]