<DefinitionAndReference>
  <Element Id="us-gaap_NetCashProvidedByUsedInInvestingActivities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityFilerCategory">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmountsThatWillBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossInNextFiscalYear">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentDisposals">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockholdersEquity">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_RevenueRecognitionPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EarningsPerShareReconciliation">
    <definition>Reconciliation of basic common shares to diluted common shares</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ForeignCurrencyFairValueHedgeLiabilityAtFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TotalNumberOfSharesAuthorizedForPurchaseUnderEmployeeStockPurchasePlan">
    <definition>Total number of shares made available for purchase under employee stock purchase plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AdditionalPaidInCapitalCommonStock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InterestExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessCombinationDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsOutstandingUpperRangeLimit">
    <definition>The ceiling of a range of exercise prices at which grantees can acquire the shares reserved for issuance under the stock option plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InterestPaidNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommonStockSharesOutstanding">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanEquitySecurities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnAccumulatedAmortizationForCapitalizedSoftware">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IntangibleAssetsGrossForeignCurrencyTranslationAdjustments">
    <definition>Reflects net changes to the recorded value of gross intangible assets for foreign currency translation adjustments needed to revise the carrying amount of gross intangible assets to fair value.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommonStockSharesIssued">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_Assets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EarningsPerShareTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsOtherRangeMaximum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_VestingScheduleForDefinedContributionPlan">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AmortizationOfIntangibleAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UnrecognizedTaxBenefitsRollForwardTextBlock">
    <definition>Disclosure of the reconciliation of the uncertain tax benefits balance from the beginning of a period to the end of a period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfDebt">
    <definition>A table or schedule providing information pertaining to total borrowings.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DerivativesPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ProvisionForDoubtfulAccounts">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentFaceAmount">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LongTermDebtNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EffectOfDilutiveStockOptionRestrictedStockAndRestrictedStockUnitSecuritiesOutstanding">
    <definition>Assumption that stock options, restricted stock or restrictive stock units outstanding at period end were exercised for computing the dilutive effect of convertible securities.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanServiceCost">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_DocumentType">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsInventory">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfEntityWideRevenueFromExternalCustomersByGeographicAreaTextBlock">
    <definition>This element may be used to capture the complete disclosure about entity-wide revenues from external customers for each geographic area if the information is not provided as part of the reportable operating segment information.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ShortTermInvestmentsPolicyTextBlock">
    <definition>This element describes an entity's accounting policy for investments in debt and equity securities that are classified as available-for-sale. These policies also may describe the entity's accounting treatment for transfers between investment categories, how the entity determines whether impairments of available-for-sale securities are other than temporary, and how the fair values of such securities are determined.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesTextBlock">
    <definition>This element represents the complete disclosure related to basis of presentation and significant accounting policies.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnCostOfSales">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FutureAmortizationExpenseYearOne">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_WeightedAverageGrantDateFairValueOfSharesForfeited">
    <definition>The weighted average fair value as of the grant date of share-based award plans other than stock option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StandardProductWarrantyAccrualPayments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_SalesRevenueNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityCommonStockSharesOutstanding">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ServiceCostIncludingContributionsByPlanParticipants">
    <definition>The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. Also includes contributions by plan participants, where applicable (primarily US Retiree Healtcare Plan).</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessCombinationsPolicy">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmortizationOfNetGainsLosses">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnGrossProfit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanActuarialNetGainsLosses">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsToAcquireShortTermInvestments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ProceedsFromIssuanceOfLongTermDebt">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsOther">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryRawMaterialsNetOfReserves">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfFutureMinimumPaymentsDueUnderNonCancelableLeasesTextBlock">
    <definition>A table or schedule providing information pertaining to future minimum rents payable as of the end of the period under non-cancelable leases with intial terms exceeding one year.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FiniteLivedIntangibleAssetsUsefulLifeMinimum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AdjustmentsToAdditionalPaidInCapitalIncreaseInValuationAllowance">
    <definition>Adjustment to additional paid-in capital for change in valuation allowance related to deferred tax assets</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInFiveFiscalYearsThereafter">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PensionAndOtherPostretirementPlansPolicyTextBlock">
    <definition>Describes an entity's accounting policy for its pension and other postretirement benefit plans. This disclosure may address (1) the types of plans sponsored by the entity, and the benefits provided by each plan (2) groups that participate in (or are covered by) each plan (3) how plan assets, liabilities and expenses are measured, including the use of any actuaries and (4) significant assumptions used by the entity to value plan assets and liabilities and how such assumptions are derived.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ChangeInUnrealizedGainLossOnForeignCurrencyFairValueHedgingInstruments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsEquitySecuritiesRangeMinimum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_RecentlyIssuedAccountingStandardsTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredIncomeTaxesAndTaxCredits">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ForeignNetOperatingLossDeferredTaxAssetsLessThan1Million">
    <definition>The tax effect as of the balance sheet date of the amount of excess of tax deductions over gross income in a year which cannot be used on the tax return of a country outside the country of domicile in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_RetainedEarningsAccumulatedDeficit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanAmountsAmortizedFromAccumulatedOtherComprehensiveIncomeInNextFiscalYearTextBlock">
    <definition>Schedule summarizing the amounts included in AOCI and to be recognized in in next year's net periodic benefit cost for defined benefit plans.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInYearOne">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TargetAllocationOfCashAndCashEquivalentsInDefinedBenefitPlanRangeMaximum">
    <definition>Target allocation maximum percentage of investments in cash and cash equivalents to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_FairValueTotalLiabilitiesMeasuredOnRecurringBasis">
    <definition>This element represents the total balance of liabilities within the statement of financial position that are measured at fair value on a recurring basis.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_Goodwill">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherLiabilitiesNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryWriteDown">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UnremittedEarningsOfForeignSubsidiaries">
    <definition>Unremitted earnings of foreign subsidiaries for the period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsGross">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsNetNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AssetsCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_NetCashProvidedByUsedInOperatingActivities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityCentralIndexKey">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_NatureOfOperations">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncreaseDecreaseInInventories">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FutureAmortizationExpenseYearTwo">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PreferredStockSharesIssued">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_AmendmentFlag">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeTextBlock">
    <definition>Schedule summarizing the amounts recognized in accumulated other comprehensive income for defined benefit plans.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CashAndCashEquivalentsPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInYearFive">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CostOfGoodsAndServicesSold">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EffectOfOneQuarterPercentagePointIncreaseInDiscountRateOnNetPeriodicBenefitCost">
    <definition>The effect of a one-quarter-percentage-point increase in the assumed discount rate on the net periodic benefit cost. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substantive plan that is the basis for the accounting.)</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_GainLossRelatedToLitigationSettlement">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ProceedsFromSaleOfShortTermInvestments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsCanceledLowerRangeLimit">
    <definition>For presentations that combine terminations, the floor of a range of the price of expired options and the price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncomplia nce with plan terms during the reporting period .</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockOptionsOutstandingRollForward">
    <definition>Disclosure of the reconciliation of the stock options outstanding balance from the beginning of a period to the end of a period. This includes the weighted-average exercise price and range of exercise prices of the shares disclosed in each line item.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_TreasuryStockValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StateAndLocalIncomeTaxExpenseBenefitContinuingOperations">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsForProceedsFromHedgeFinancingActivities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TargetAllocationOfCashAndCashEquivalentsInDefinedBenefitPlanRangeMinimum">
    <definition>Target allocation minimum percentage of investments in cash and cash equivalents to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_WeightedAverageInterestRate">
    <definition>Reflects the calculation as of the balance-sheet date of the average interest rate weighted by the amount of total debt outstanding by type or by instrument at that time.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanFairValueOfPlanAssetsUnobservableInputReconciliationTextBlock">
    <definition>This element represents, for the fair value measurement of defined benefit plan assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (net); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs).</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanContributionsByPlanParticipants">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InvestmentIncomeInterest">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_VoluntaryPrepaymentOfLongTermDebt">
    <definition>Amount of long-term debt voluntarily paid off before debt maturity date.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LiabilitiesAndStockholdersEquity">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncreaseDecreaseInAccountsReceivable">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_InventoryNetOfReservesTextBlock">
    <definition>Disclosure of the carrying value of inventory, net of reserves.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInYearTwo">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessAcquisitionProFormaInformationTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnGrossCarryingValueOfCapitalizedSoftware">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FutureAmortizationExpenseYearThree">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PreferredStockValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_LicenseFeesPaidLessThan1Million">
    <definition>Costs paid for licensing arrangements, including, but not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark, which are less than $1 million.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DescriptionOfBusinessAndOrganizationTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsLiabilitiesNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OperatingIncomeLoss">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UnrecognizedDomesticFederalAndStateNetOperatingLossCarryforwardDeferredTaxAssets">
    <definition>The amount of the deferred tax asset related to U.S. federal and state operating loss carryforwards which was not recognized because of the exceptions to comprehensive recognition of deferred taxes.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsDebtSecuritiesRangeMinimum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ContractNotionalAmountOfInterestRateSwapAgreements">
    <definition>Notional amount stated for each interest rate derivative designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TargetAllocationOfForeignEquitySecuritiesWithinTotalEquitySecuritiesInDefinedBenefitPlan">
    <definition>Target allocation of foreign equity securities in equity portfolio of defined benefit plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsCanceledUpperRangeLimit">
    <definition>For presentations that combine terminations, the ceiling of a range of the price of expired options and the price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncomplia nce with plan terms during the reporting period .</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ComponentsOfPlanAssetCategories">
    <definition>The percentage of the fair value of investment to the fair value of total plan asset category held as of the measurement date.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedContributionPlanCostRecognized">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccountingChangesAndErrorCorrectionsTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OtherIntangibleAssetsPolicyTextBlock">
    <definition>Describes an entity's accounting policy for intangible assets. This accounting policy may address both intangible assets subject to amortization and those that are not. The following also may be disclosed: (1) a description of intangible assets (2) the estimated useful lives of those assets (3) the amortization method used (4) how the entity assesses and measures impairment of such assets (5) how future cash flows are estimated (6) how the fair values of such asset are determined.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_CumulativePreTaxUnrealizedGainLossOnInterestRateSwapAgreementsRecordedInAccumulatedOtherComprehensiveIncome">
    <definition>Amount of unrealized gain (loss) related to the increase (decrease) in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income during the period to the extent that the cash flow hedge was determined to be effective.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_GoodwillPolicyTextBlock">
    <definition>Describes an entity's accounting policy for goodwill. This accounting policy also may address how an entity assesses and measures impairment of goodwill, how reporting units are determined, how goodwill is allocated to such units, and how the fair values of the reporting units are determined.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanTargetAssetAllocationsTextBlock">
    <definition>Schedule of target asset investment allocations, including the target ranges.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PurchasedIntangiblesAmortization">
    <definition>The aggregate expense charged against earnings to allocate the cost of intangible assets acquired (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnAccumulatedOtherComprehensiveIncome">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsOfDebtIssuanceCosts">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeLossFromContinuingOperationsPerBasicShare">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AccountsReceivableAndAllowanceForDoubtfulAccountsPolicyTextBlock">
    <definition>Describes an entity's accounting policy for trade and other accounts receivables. This disclosure may include the basis at which such receivables are carried in the entity's statements of financial position (for example, net realizable value), how the entity determines the level of its allowance for doubtful accounts, when impairments, charge-offs or recoveries are recognized, and the entity's income recognition policies for such receivables, including its treatment of related fees and costs, its treatment of premiums, discounts or unearned income, when accrual of interest is discontinued, how the entity records payments received on nonaccrual receivables and its policy for resuming accrual of interest on such receivables. If the enterprise holds a large number of similar loans, disclosure may include the accounting policy for the anticipation of prepayments and significant assumptions underlying prepayment estimates for amortization of premiums, discounts, and nonrefundable fees and costs.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AcquiredIntangibleAssets">
    <definition>The aggregate amount assigned to a major class of intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredIncomeTaxExpenseBenefit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UncertainIncomeTaxReportingPositionsPolicyTextBlock">
    <definition>Describes an entity's accounting policy for tax positions taken in the Company's tax return filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of contingencies related to income taxes.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccruedIncomeTaxesCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DepreciationAndCapitalizedSoftwareDeferredTaxAssets">
    <definition>The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from depreciation and capitalized software amortization.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_SharesIssued">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsNetCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsExercisedLowerRangeLimit">
    <definition>The floor of a range of exercise prices at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ComponentsOfDeferredTaxAssetsAndLiabilitiesTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LiabilitiesNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnProvisionForIncomeTaxes">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommitmentsAndContingencies2009">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmortizationOfNetPriorServiceCostCredit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsEquitySecuritiesRangeMaximum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_Liabilities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsExercisedUpperRangeLimit">
    <definition>The ceiling of a range of exercise prices at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessAcquisitionCostOfAcquiredEntityCashPaid">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsUnderstatementOfAmortizationExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsGrantedLowerRangeLimit">
    <definition>The floor of a range of the price of granted options and the price at which grantees can acquire the underlying shares with respect to stock options that were granted during the reporting period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PreferredSharePurchaseRightsRedemptionProvision">
    <definition>Description of how the preferred share purchase rights may be redeemed by the board of directors.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_MaximumContributionAllowedUnderEmployeeStockPurchasePlanAsOfEmployeesEarnings">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityCurrentReportingStatus">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherAssetsCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfIntangibleAssetsByMajorClass">
    <definition>Disclosure of the carrying value of intangible assets (indefinite and finite), excluding goodwill, in total and by major class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of the company.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_RecentlyAdoptedAccountingStandardsTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanNetPeriodicBenefitCostTextBlock">
    <definition>Schedule of the components of net periodic benefit cost for defined benefit plans for the period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityWellKnownSeasonedIssuer">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentGross">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanOtherPlanAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnDeferredTaxLiabilities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_RestrictedStockUnitsUnvestedRollForward">
    <definition>Disclosure of the reconciliation of the restricted stock units unvested balance from the beginning of a period to the end of a period. This includes the weighted-average price of the shares disclosed in each line item.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_NotionalAmountOfForeignCurrencyFairValueHedgeDerivatives">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EffectOfDilutiveStockOptionRestrictedStockAndRestrictedStockUnitSecuritiesExercisedAndCancellations">
    <definition>Assumption that stock options, restricted stock or restrictive stock units exercised and cancelled during the period were exercised at the beginning of the period for computing the dilutive effect of convertible securities.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_InternalUseSoftwarePolicyTextBlock">
    <definition>Describes an entity's accounting policy for costs incurred when both (1) the software is acquired, internally developed, or modified solely to meet the entity's internal needs, and (2) during the software's development or modification, no substantive plan exists or is being developed to market the software externally.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockBasedCompensationPolicyTextBlock">
    <definition>This element describes an entity's accounting policy for stock option and stock incentive plans. This disclosure may include (1) the types of stock option or incentive plans sponsored by the entity (2) the groups that participate in (or are covered by) each plan (3) significant plan provisions and (4) how stock compensation is measured, and the methodologies and significant assumptions used to determine that measurement.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UnrecognizedDomesticFederalAndStateNetOperatingLossCarryforwardDeferredTaxAssetsPreTax">
    <definition>The pre-tax amount of the deferred tax asset related to U.S. federal and state operating loss carryforwards which was not recognized because of the exceptions to comprehensive recognition of deferred taxes.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockBasedCompensationExpenseCapitalized">
    <definition>Represents the compensation cost capitalized as of the balance sheet date arising from share-based compensation arrangements (for example, shares of stock, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ScheduleOfShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_MaximumPercentageOfNetSalesToIndividualCustomer">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockRepurchaseProgramRemainingAmountAuthorizedForFuturePurchases">
    <definition>Total remaining dollar amount authorized for future share repurchase under programs authorized by an entity's Board of Directors.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityRegistrantName">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AdditionalInterestExpenseRecordedFromInterestRateSwapAgreements">
    <definition>Additional interest expense recorded in earnings from interest rate swap agreements to hedge the risk to earnings associated with fluctuations in interest rates related to outstanding U.S. dollar floating rate debt.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StandardProductWarrantyAccrual">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInYearThree">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsValuationAllowance">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsForRepurchaseOfCommonStock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanEstimatedFutureBenefitPaymentsTextBlock">
    <definition>The benefits (as of the date of the latest statement of financial position presented), expected to be paid in each of the next five years, and in the aggregate for the next succeeding five years. The expected benefits should be estimated based on the same assumptions used to measure the company's benefit obligation at the end of the year and should include estimated future employee service.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxesPaidNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_SellingGeneralAndAdministrativeExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PreferredSharePurchaseRightsNumberOfSecuritiesCalled">
    <definition>The specified number of securities that each class of warrants or rights outstanding give the holder the right but not the obligation to purchase from the issuer at a specific price, on or before a certain date.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedContributionPlanCompanyMatchingContributionRate">
    <definition>The rate at which the Company makes matching contributions to the 401(k) plan up to the limit of 6% of eligible pay.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTerm">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_TreasuryStockShares">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_CompensationExpenseRelatedToEmployeeStockPurchasePlanLessThan1Million">
    <definition>The amount of plan compensation cost recognized during the period, when the amount is less than $1 million.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanVestingSchedule">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LongTermInvestments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AllocatedShareBasedCompensationExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanAmountsRecognizedInBalanceSheetTextBlock">
    <definition>Schedule summarizing the amounts recognized in the consolidated balance sheet for defined benefit plans.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxExpenseBenefit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AdvertisingCostsPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CashEquivalentsAtCarryingValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessAcquisitionPurchasePriceAllocationNoncurrentLiabilitiesLongTermDebt">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PercentOfNetSalesToPharmaceuticalIndustry">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ForeignNetOperatingLossDeferredTaxAssetsPreTax">
    <definition>Pre-tax amount of the tax effect as of the balance sheet date of the amount of excess of tax deductions over gross income in a year which cannot be used on the tax return of a country outside the country of domicile in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_WeightedAverageExercisePriceOfOptionsExercised">
    <definition>The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CostOfServices">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EmployeeServiceShareBasedCompensationUnrecognizedCompensationCostsOnNonvestedAwardsWeightedAveragePeriodOfRecognition">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_NetCashProvidedByUsedInFinancingActivities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_GainLossOnForeignCurrencyFairValueHedgeDerivatives">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsGrantedUpperRangeLimit">
    <definition>The ceiling of a range of the price of granted options and the price at which grantees can acquire the underlying shares with respect to stock options that were granted during the reporting period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccountsReceivableNetCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_RelevantDataUsedToDetermineValueOfStockOptionsGrantedDuringPeriodTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanInterestCost">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FiniteLivedIntangibleAssetsUsefulLifeMaximum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsDebtSecuritiesRangeMaximum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EmployeeStockOwnershipPlanESOPCompensationExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationDating">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EstimatedFutureEmployerContributionsToDefinedBenefitPlansInNextFiscalYearRangeMaximum">
    <definition>The employer's best estimate, as soon as it can be reasonably determined, of the maximum contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_WarrantyAccrualRollForwardTextBlock">
    <definition>Disclosure of the reconciliation of the warranty accrual balance from the beginning of a period to the end of a period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxReconciliationOtherAdjustments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_SegmentReportingPolicyTextBlock">
    <definition>Describes the entity's policy for segment reporting.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CostOfGoodsSold">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EmployeeRelatedLiabilitiesCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_WatersRestorationPlanAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardTermsOfAward">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UnauditedQuarterlyResultsTextBlock">
    <definition>Tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IrishTaxRate">
    <definition>The statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate shall be the regular tax rate if there are alternative tax systems.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentInterestRateTerms">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_FairValueMeasurementsPolicyTextBlock">
    <definition>Describes an entity's accounting policy for determining the fair value of its assets and liabilities.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnNetIncome">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_WeightedAverageExercisePriceOfOptionsGranted">
    <definition>The weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_Depreciation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CashAndCashEquivalentsAtCarryingValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsEquityMethodInvestments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsImpactOnIncomeFromOperationsBeforeIncomeTaxes">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentCallFeature">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_DocumentFiscalPeriodFocus">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PreferredStockSharesAuthorized">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_SegmentReportingDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FutureAmortizationExpenseYearFive">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTextBlock">
    <definition>This element represents the disclosure related to assets and liabilities, including financial instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LeaseAndRentalExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EffectiveIncomeTaxRateContinuingOperations">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ForeignCurrencyFairValueHedgeAssetAtFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DepreciationAndCapitalizedSoftwareDeferredTaxLiabilities">
    <definition>The amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax basis of capital assets and capitalized softward and the basis of capital assets and capitalized software computed in accordance with generally accepted accounting principles. The difference in basis, attributable to different capitalization of costs, depreciation, or amortization methodologies, will increase future taxable income when such basis difference is realized. Capital assets include but are not limited to assets such as land, real estate, leasehold improvements, machinery and equipment and furniture and fixtures.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DescriptionOfDefinedContributionPensionAndOtherPostretirementPlans">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CurrentIncomeTaxExpenseBenefit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanFairValueMeasurementOfPlanAssetsTextBlock">
    <definition>This element represents the disclosure related to defined benefit plan assets, including financial instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IncreaseInDeferredRevenueAndCustomerAdvances">
    <definition>The net change during the reporting period, excluding the portion taken into income, in the liability reflecting services yet to be performed by the reporting entity for which cash or other forms of consideration was received or recorded as a receivable and the net change during the reporting period in the amount of prepayments by customers for goods or services to be provided at a later date.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EffectOfOneQuarterPercentagePointIncreaseInReturnOnAssetsOnNetPeriodicBenefitCost">
    <definition>The effect of a one-quarter-percentage-point increase in the assumed return on assets on the net periodic benefit cost. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substantive plan that is the basis for the accounting.)</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ComprehensiveIncomePolicyTextBlock">
    <definition>Describes an entity's accounting policy for presentation of comprehensive income.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DomesticFederalAndStateNetOperatingLossCarryforwardDeferredTaxAssets">
    <definition>The tax effect as of the balance sheet date of the amount of excess of tax deductions over gross income in a year which cannot be used on the tax return of the country of domicile and the tax returns of a state or local jurisdication in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_SalesRevenueServicesNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentUsefulLifeMinimum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxDisclosureTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_NetDecreaseInUnrecognizedTaxBenefitsResultingFromSettlementsWithTaxingAuthorities">
    <definition>The decreases in unrecognized tax benefits resulting from settlements with taxing authorities, offset by the amount of the audit settlement.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedContributionPlanCompanyMatchingContributionLimit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TotalDebt">
    <definition>Sum of the carrying values as of the balance sheet date of all debt.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanAccumulatedBenefitObligationTextBlock">
    <definition>Schedule of the change in accumulated benefit obligation for defined benefit plans for the period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PreferredSharePurchaseRightsTriggeringEvent">
    <definition>The event that triggers the preferred share purchase rights to become exercisable.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TotalNumberOfSharesPurchasedUnderEmployeeStockPurchasePlan">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_CumulativeNetPreTaxGainsLossesOnForwardForeignExchangeContracts">
    <definition>Total amount of realized and unrealized gain (loss) from the increase (decrease) in fair value of foreign currency derivatives and nonderivative instruments designated as fair value hedging instruments which were recognized in earnings, net of offsets by the gain (loss) on the hedged item to the extent that the fair value hedge was determined to be effective.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PercentagePointChangeInEffectiveTaxRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LiabilitiesCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfPropertyPlantAndEquipmentTextBlock">
    <definition>Table of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, building and production equipment.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryFinishedGoodsNetOfReserves">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_Litigation">
    <definition>This element represents the complete disclosure related to litigation.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommonStockValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IntangibleAssetsAccumulatedAmortizationForeignCurrencyTranslationAdjustments">
    <definition>Reflects net changes to the recorded value of accumulated amortization for intangible assets for foreign currency translation adjustments needed to revise the carrying amount of accumulated amortization for intangible assets to fair value.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DeductionsFromAllowanceForDoubtfulAccountsAndSalesReturns">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanActualPlanAssetAllocationsTextBlock">
    <definition>Schedule of actual plan asset invesment mix for defined benefit plans.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_CurrentFiscalYearEndDate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitFundedStatusOfPlanTextBlock">
    <definition>Schedule summarizing the funded status of defined benefit plans.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanFairValueOfPlanAssetsTextBlock">
    <definition>Schedule of the change in the fair value of plan assets for defined benefit plans for the period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanFundedStatusOfPlan">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EmployeeServiceShareBasedCompensationUnrecognizedCompensationCostsOnNonvestedAwards">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PurchasePriceCalculationForSharesOfStockUnderEmployeeStockPurchasePlan">
    <definition>Calcuation for determining the stock price for shares purchased under employee stock purchase plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OutOfPeriodAdjustmentsOverstatementOfIncomeTaxExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_EarningsPerSharePolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ComponentsOfIncomeTaxesTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_DocumentPeriodEndDate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IndefiniteLivedIntangiblesDeferredTaxLiabilities">
    <definition>The cumulative amount of the estimated future tax effects attributable to the difference between the tax basis of indefinite-lived intangible assets and the basis of indefinite-lived intangible assets computed in accordance with generally accepted accounting principles.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FiniteLivedIntangibleAssetsAverageUsefulLife">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_OtherComprehensiveIncomeNetForeignCurrencyAdjustments">
    <definition>Sum of foreign currency translation and net appreciation and realized gains on derivative instruments related to foreign currency.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_SalesRevenueGoodsNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TargetMinimumReturnOnAssets">
    <definition>The Company's long-term investment objectives for the U.S. defined benefit plans as a % above the one-year constant maturity Treasury bond yield over reasonable measurement periods and based on reasonable market cycles.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ConsolidationsPolicyTextBlock">
    <definition>Describes an entity's accounting policy for its subsidiaries or other investments that are consolidated, including the accounting treatment for intercompany accounts or transactions and any noncontrolling interest.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EmployeeDefinedContributionPlanContributionsUpperRangeLimit">
    <definition>Upper range limit of employee contributions, as a percent of eligible pay on a pre-tax basis.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentCovenantDescription">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommonStockSharesAuthorized">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxLiabilities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_FutureMinimumRentsPayableInFiveYearsAndThereafter">
    <definition>For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due after the fourth year from the balance sheet date on leases defined as operating.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccruedIncomeTaxesNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EquityAndCostMethodInvestmentsPolicyTextBlock">
    <definition>This element describes an entity's application of the equity method of accounting to investments in common stock or other interests including unconsolidated domestic subsidiaries, corporate joint ventures, noncontrolling interests in real estate ventures, limited partnerships, and limited liability companies. Additionally, this element describes the entity's application of the cost method to equity investments or other interests that are not consolidated or accounted for under the equity method of accounting. The description provided may include a description of how equity method or cost investments are assessed for impairment.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IncreaseInOtherUncertainTaxBenefits">
    <definition>The amount of increases in unrecognized tax benefits resulting from changes in all other tax positions.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EstimatedFutureEmployerContributionsToDefinedBenefitPlansInNextFiscalYearRangeMinimum">
    <definition>The employer's best estimate, as soon as it can be reasonably determined, of the minimum contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_DocumentFiscalYearFocus">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanDebtSecurities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfComprehensiveIncome">
    <definition>Schedule of the components of comprehensive income during the period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessAcquisitionPurchasePriceAllocationIntangibleAssetsNotAmortizable">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_TreasuryStockValueAcquiredCostMethod">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtInstrumentInterestRateStatedPercentage">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_CashAndCashEquivalentsInDefinedBenefitPlan">
    <definition>The percentage of the fair value of cash and cash equivalents to the fair value of total plan assets held as of the measurement date.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StandardProductWarrantyAccrualWarrantiesIssued">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_FutureAmortizationExpenseYearFour">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPeriodIncreaseDecrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredRevenueAndCreditsCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AllowanceForDoubtfulAccountsAndSalesReturnsRollForwardTextBlock">
    <definition>Disclosure of the reconciliation of the allowance for doubtful accounts and sales returns balance from the beginning of a period to the end of a period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanBenefitsPaid">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_PercentOfNetSalesDerivedFromOperationsOutsideUnitedStates">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherAssetsNoncurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_SoftwareDevelopmentCostsForSoftwareToBeSoldPolicyTextBlock">
    <definition>Describes an entity's accounting policy for costs incurred to (1) establish the technological feasibility of a computer software product to be sold, leased, or otherwise marketed; and (2) produce product masters after establishing technological feasibility. This accounting policy also may apply to purchased computer software. This policy also may address the entity's amortization policy for its capitalized computer software costs and how it evaluates such capitalized costs for impairment.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_OtherLiabilitiesCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PreferredStockParOrStatedValuePerShare">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsEquitySecurities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IntangibleAssetsNetExcludingGoodwill">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ExercisePriceRangeOfOptionsOutstandingLowerRangeLimit">
    <definition>The floor of a range of exercise prices at which grantees can acquire the shares reserved for issuance under the stock option plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentNet">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ResearchAndDevelopmentExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_TreasuryStockSharesAcquired">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InventoryWorkInProcessNetOfReserves">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsForProceedsFromProductiveAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsDebtSecurities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanInterestCreditingRate">
    <definition>Description of how the interest crediting rate is determined for a defined benefit plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_NetOperatingLossCarryforwardsAndCreditsDeferredTaxAssets">
    <definition>The sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset, offset by The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncreaseDecreaseInOtherOperatingAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AcquiredFiniteLivedIntangibleAssetWeightedAverageUsefulLife">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_TargetAllocationOfCashAndCashEquivalentsInDefinedBenefitPlan">
    <definition>Target allocation percentage of investments in cash and cash equivalents to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ScheduleOfEntityWideLongLivedAssetsByGeographicAreaTextBlock">
    <definition>This element may be used to capture the complete disclosure about entity-wide long-lived assets for each geographic area if the information is not provided as part of the reportable operating segment information.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShortTermInvestments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockBasedCompensationExpenseCapitalizedLessThan1Million">
    <definition>Represents the compensation cost capitalized as of the balance sheet date arising from share-based compensation arrangements (for example, shares of stock, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees, where the balance is less than $1 million.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxLiabilitiesOther">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsForLegalSettlements">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInYearFour">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanBenefitObligation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_CommonStockParOrStatedValuePerShare">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_RepaymentsOfLongTermDebt">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AdvertisingExpense">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanOtherInformation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ComprehensiveIncomeNoteTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_GrossProfit">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanTargetAllocationPercentageOfAssetsOtherRangeMinimum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AdditionsToAllowanceForDoubtfulAccountsAndSalesReturns">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ForeignIncomeTaxExpenseBenefitContinuingOperations">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanContributionsByEmployer">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_QuarterlyFinancialInformationTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockBasedCompensationCostsLessThan1Million">
    <definition>Share-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset, where the expens is less than $1 million.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityPublicFloat">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_EmployeeDefinedContributionPlanContributionsLowerRangeLimit">
    <definition>Lower range limit of employee contributions, as a percent of eligible pay on a pre-tax basis.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeNetGainLossBeforeTax">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_CapitalizedCostsForSofwareDevelopedForInternalUse">
    <definition>Unamortized costs incurred for development of computer software, which is to be used internally and not sold to customers.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="dei_EntityVoluntaryFilers">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_UseOfEstimatesAndJudgmentsTextBlock">
    <definition>Provides an entity's explanation that the preparation of financial statements in conformity with generally accepted accounting principles requires the use of management estimates. Estimates used in the determination of carrying amounts of assets or liabilities, or in disclosure of gain or loss contingencies should be disclosed if known information available prior to issuance of the financial statements indicates that both of these criteria are met: (1) It is at least reasonably possible that the estimate of the effect on the financial statements of a condition, situation, or set of circumstances that existed at the date of the financial statements will change in the near term (less than one year from the date of issuance) due to one or more future confirming events, and (2) The effect of the change would be material to the financial statements. The disclosure should indicate the nature of the uncertainty and include an indication that it is at least reasonably possible that a change in the estimate will occur in the near term. Disclosure of the factors that cause the estimate to be sensitive to change also is encouraged. Entities also may identify those areas that are subject to significant estimates.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DebtPolicyTextBlock">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillAmount">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_UnrecognizedTaxBenefits">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ResearchAndDevelopmentExpensesPolicyTextBlock">
    <definition>Describes an entity's accounting policy for costs it has incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_StockRepurchaseProgramAuthorizationAmount">
    <definition>Total dollar amount authorized for share repurchase program authorized by an entity's Board of Directors.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_IntangibleAssetsGross">
    <definition>Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_SpecialContributionToRetirementPlan">
    <definition>One-time contribution to the defined contribution plan approved by the Company's Board of Directors as part of the amendments made to the defined contribution plan.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_ProductWarrantyPolicyTextBlock">
    <definition>Description for the guarantor's accounting for standard warranties including the methodology for measuring the liability.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_AccountsPayableCurrent">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_DeferredTaxAssetsOther">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_AllowancesForDoubtfulAccountsAndSalesReturns">
    <definition>A valuation allowance for trade and other receivables that are expected to be uncollectible and sales returns that are expected to occur.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_FairValueTotalAssetsMeasuredOnRecurringBasis">
    <definition>This element represents the total balance of assets within the statement of financial position that measured at fair value on a recurring basis.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="wat_DefinedBenefitPlanProjectedBenefitObligationTextBlock">
    <definition>Schedule of the change in projected benefit obligation for defined benefit plans for the period.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
  <Element Id="us-gaap_PropertyPlantAndEquipmentUsefulLifeMaximum">
    <definition>No authoritative reference available.</definition>
    <reference>No authoritative reference available.</reference>
  </Element>
</DefinitionAndReference>
