2.2.0.7 true Basis of Presentation and Summary of Significant Accounting Policies (Details) (USD $) 40100 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details) true false Share data in Millions false false 1 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 EPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 EPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 3 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 EPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 4 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 EPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 5 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 EPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 6 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 7 USD true false false false Significant Other Observable Inputs (Level 2) us-gaap_FairValueAssetsMeasuredOnRecurringBasisDisclosureItemsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_FairValueInputsLevel2Member us-gaap_FairValueAssetsMeasuredOnRecurringBasisDisclosureItemsAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 8 USD true false false false Significant Other Observable Inputs (Level 2) us-gaap_FairValueAssetsMeasuredOnRecurringBasisDisclosureItemsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_FairValueInputsLevel2Member us-gaap_FairValueAssetsMeasuredOnRecurringBasisDisclosureItemsAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 9 USD true false false false Significant Other Observable Inputs (Level 2) us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_FairValueInputsLevel2Member us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 10 USD true false false false Significant Other Observable Inputs (Level 2) us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_FairValueInputsLevel2Member us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 11 USD true false false false February 2007 Program [Member] wat_StockRepurchaseProgramAxis xbrldi http://xbrl.org/2006/xbrldi wat_February2007ProgramMember wat_StockRepurchaseProgramAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 12 USD true false false false February 2007 Program [Member] wat_StockRepurchaseProgramAxis xbrldi http://xbrl.org/2006/xbrldi wat_February2007ProgramMember wat_StockRepurchaseProgramAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 13 USD true false false false February 2009 Program [Member] wat_StockRepurchaseProgramAxis xbrldi http://xbrl.org/2006/xbrldi wat_February2009ProgramMember wat_StockRepurchaseProgramAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 14 USD true false false false February 2009 Program [Member] wat_StockRepurchaseProgramAxis xbrldi http://xbrl.org/2006/xbrldi wat_February2009ProgramMember wat_StockRepurchaseProgramAxis explicitMember Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 15 USD true false false false February 2009 Program [Member] wat_StockRepurchaseProgramAxis xbrldi http://xbrl.org/2006/xbrldi wat_February2009ProgramMember wat_StockRepurchaseProgramAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ 3 Fair Value of Assets Measured on a Recurring Basis [Line Items] 1 us-gaap_FairValueAssetsMeasuredOnRecurringBasisFinancialStatementCaptionsLineItems us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:stringItemType string Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. false 4 Cash equivalents 2 us-gaap_CashEquivalentsAtCarryingValue us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 true true false false 106273000 106273000 false false false 2 false false false false 0 0 false false false 3 true true false false 106273000 106273000 false false false 4 false false false false 0 0 false false false 5 true true false false 181925000 181925000 false false false 6 false false false false 0 0 false false false 7 true true false false 106273000 106273000 true false false 8 true true false false 181925000 181925000 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash equivalents may be reported as cash equivalents, while legally restricted equivalents held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular equivalents should not be reported as part of unrestricted cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 false 5 Short-term investments 2 us-gaap_ShortTermInvestments us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 false true false false 574306000 574306000 false false false 2 false false false false 0 0 false false false 3 false true false false 574306000 574306000 false false false 4 false false false false 0 0 false false false 5 false true false false 289146000 289146000 false false false 6 false false false false 0 0 false false false 7 false true false false 574306000 574306000 true false false 8 false true false false 289146000 289146000 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 false 6 Waters Retirement Restoration Plan assets 2 us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 false true false false 18771000 18771000 false false false 2 false false false false 0 0 false false false 3 false true false false 18771000 18771000 false false false 4 false false false false 0 0 false false false 5 false true false false 17955000 17955000 false false false 6 false false false false 0 0 false false false 7 false true false false 18771000 18771000 true false false 8 false true false false 17955000 17955000 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph c false 7 Foreign currency exchange contract agreements, assets 2 us-gaap_ForeignCurrencyFairValueHedgeAssetAtFairValue us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 375000 375000 false false false 2 false false false false 0 0 false false false 3 false true false false 375000 375000 false false false 4 false false false false 0 0 false false false 5 false true false false 237000 237000 false false false 6 false false false false 0 0 false false false 7 false true false false 375000 375000 true false false 8 false true false false 237000 237000 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of all derivative assets designated as foreign currency fair value hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 true 8 Fair value of total assets measured on a recurring basis 2 wat_FairValueTotalAssetsMeasuredOnRecurringBasis wat false debit instant This element represents the total balance of assets within the statement of financial position that measured at fair value on... false false false false false false false false false false false totallabel false 1 false true false false 699725000 699725000 false false false 2 false false false false 0 0 false false false 3 false true false false 699725000 699725000 false false false 4 false false false false 0 0 false false false 5 false true false false 489263000 489263000 false false false 6 false false false false 0 0 false false false 7 false true false false 699725000 699725000 true false false 8 false true false false 489263000 489263000 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the total balance of assets within the statement of financial position that measured at fair value on a recurring basis. No authoritative reference available. true 10 Fair Value of Liabilities Measured on a Recurring Basis [Line Items] 1 us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisFinancialStatementCaptionsLineItems us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:stringItemType string Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. false 11 Foreign currency exchange contract agreements, liabilities 2 us-gaap_ForeignCurrencyFairValueHedgeLiabilityAtFairValue us-gaap true credit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 664000 664000 false false false 2 false false false false 0 0 false false false 3 false true false false 664000 664000 false false false 4 false false false false 0 0 false false false 5 false true false false 400000 400000 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false true false false 664000 664000 true false false 10 false true false false 400000 400000 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of all derivative liabilities designated as foreign currency fair value hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 true 12 Fair value of total liabilities measured on a recurring basis 2 wat_FairValueTotalLiabilitiesMeasuredOnRecurringBasis wat false credit instant This element represents the total balance of liabilities within the statement of financial position that are measured at fair... false false false false false false false false false false false totallabel false 1 false true false false 664000 664000 false false false 2 false false false false 0 0 false false false 3 false true false false 664000 664000 false false false 4 false false false false 0 0 false false false 5 false true false false 400000 400000 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false true false false 664000 664000 true false false 10 false true false false 400000 400000 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the total balance of liabilities within the statement of financial position that are measured at fair value on a recurring basis. No authoritative reference available. true 14 Stock Repurchase Program [Line Items] 1 wat_StockRepurchaseProgramLineItems wat false na duration Line items represent financial concepts included in a table. These concepts are used to disclose reportable information... false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:stringItemType string Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. false 15 Stock repurchase program authorization amount 2 wat_StockRepurchaseProgramAuthorizationAmount wat false debit instant Total dollar amount authorized for share repurchase program authorized by an entity's Board of Directors. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false true false false 500000000 500000000 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false true false false 500000000 500000000 true false false xbrli:monetaryItemType monetary Total dollar amount authorized for share repurchase program authorized by an entity's Board of Directors. No authoritative reference available. false 16 Treasury stock shares acquired 2 us-gaap_TreasuryStockSharesAcquired us-gaap true na duration No definition available. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false true false false 1400000 1.4 true false false 12 false false false false 0 0 true false false 13 false true false false 3800000 3.8 true false false 14 false true false false 2200000 2.2 true false false 15 false false false false 0 0 true false false xbrli:sharesItemType shares Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 false 17 Treasury stock value acquired 2 us-gaap_TreasuryStockValueAcquiredCostMethod us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false true false false 53000000 53000000 true false false 12 false false false false 0 0 true false false 13 false true false false 241000000 241000000 true false false 14 false true false false 103000000 103000000 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 1 -Section B -Paragraph 7 -Subparagraph b false 18 Summary of Derivative Instruments by Risk Exposure [Abstract] 0 us-gaap_SummaryOfDerivativeInstrumentsByRiskExposureAbstract us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:stringItemType string No definition available. false 19 Contract notional amount of interest rate swap agreements 1 wat_ContractNotionalAmountOfInterestRateSwapAgreements wat false debit instant Notional amount stated for each interest rate derivative designated as hedging instruments in cash flow hedges. Notional... false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false true false false 50000000 50000000 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary 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. No authoritative reference available. false 20 Interest rate swap liability at fair value 1 us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false false false false 0 0   false false false 2 false false false false 0 0 false false false 3 false false false false 0 0   false false false 4 false false false false 0 0 false false false 5 false false false false 0 0     false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 17 false 21 Cumulative pre-tax unrealized gain (loss) on interest rate swap agreements recorded in accumulated other comprehensive income 1 wat_CumulativePreTaxUnrealizedGainLossOnInterestRateSwapAgreementsRecordedInAccumulatedOtherComprehensiveIncome wat false credit duration Amount of unrealized gain (loss) related to the increase (decrease) in fair value of interest rate derivatives designated as... false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false true false false 1000000 1000000 false false false 3 false false false false 0 0 false false false 4 false true false false 2000000 2000000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary 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. No authoritative reference available. false 22 Additional interest expense recorded from interest rate swap agreements 1 wat_AdditionalInterestExpenseRecordedFromInterestRateSwapAgreements wat false debit duration Additional interest expense recorded in earnings from interest rate swap agreements to hedge the risk to earnings associated... false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false true false false 2000000 2000000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary 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. No authoritative reference available. false 23 Additional interest expense recorded from interest rate swap agreements, less than $1 million 1 wat_AdditionalInterestExpenseRecordedFromInterestRateSwapAgreementsLessThan1Million wat false na duration Additional interest expense recorded in earnings from interest rate swap agreements to hedge the risk to earnings associated... false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 less than $1 million less than $1 million false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:stringItemType string 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. No authoritative reference available. false 24 Notional amount of forward foreign exchange contracts 1 us-gaap_NotionalAmountOfForeignCurrencyFairValueHedgeDerivatives us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 false true false false 152000000 152000000 false false false 2 false false false false 0 0 false false false 3 false true false false 152000000 152000000 false false false 4 false false false false 0 0 false false false 5 false true false false 138000000 138000000 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Aggregate notional amount of all foreign currency derivatives designated as hedging instruments in fair value hedges. Notional amount refers to the number of currency units specified in the foreign currency derivative contract. No authoritative reference available. false 25 Forward foreign exchange contract assets 1 us-gaap_ForeignCurrencyFairValueHedgeAssetAtFairValue us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 false true false false 375000 375000 false false false 2 false false false false 0 0 false false false 3 false true false false 375000 375000 false false false 4 false false false false 0 0 false false false 5 false true false false 237000 237000 false false false 6 false false false false 0 0 false false false 7 false true false false 375000 375000 true false false 8 false true false false 237000 237000 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of all derivative assets designated as foreign currency fair value hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 false 26 Forward foreign exchange contract liabilities 1 us-gaap_ForeignCurrencyFairValueHedgeLiabilityAtFairValue us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 664000 664000 false false false 2 false false false false 0 0 false false false 3 false true false false 664000 664000 false false false 4 false false false false 0 0 false false false 5 false true false false 400000 400000 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false true false false 664000 664000 true false false 10 false true false false 400000 400000 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of all derivative liabilities designated as foreign currency fair value hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 false 27 Cumulative net pre-tax gains (losses) on forward foreign exchange contracts 1 wat_CumulativeNetPreTaxGainsLossesOnForwardForeignExchangeContracts wat false credit duration Total amount of realized and unrealized gain (loss) from the increase (decrease) in fair value of foreign currency... false false false false false false false false false false false false 1 false true false false 2000000 2000000 false false false 2 false true false false -4000000 -4000000 false false false 3 false true false false -5000000 -5000000 false false false 4 false true false false 6000000 6000000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary 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. No authoritative reference available. false 28 Gain (loss) on closed forward foreign exchange contracts 1 us-gaap_GainLossOnForeignCurrencyFairValueHedgeDerivatives us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false 2000000 2000000 false false false 2 false true false false -4000000 -4000000 false false false 3 false true false false -5000000 -5000000 false false false 4 false true false false 5000000 5000000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Amount of 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 45 -Subparagraph a(1) false 29 Change in unrealized gain (loss) on open forward foreign exchange contracts 1 us-gaap_ChangeInUnrealizedGainLossOnForeignCurrencyFairValueHedgingInstruments us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false true false false 1000000 1000000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Amount of 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 45 -Subparagraph a(1) false 30 Warranty Accrual Roll Forward [Abstract] 0 us-gaap_MovementInStandardProductWarrantyAccrualRollForward us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:stringItemType string A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. false 31 Accrued warranty liability, balance at beginning of period 1 us-gaap_StandardProductWarrantyAccrual us-gaap true credit instant No definition available. false false false false false false false false true false false periodstartlabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false 10109000 10109000 false false false 4 false true false false 10276000 10276000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 14 -Subparagraph b false 32 Accruals for warranties 1 us-gaap_StandardProductWarrantyAccrualWarrantiesIssued us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false 4849000 4849000 false false false 4 false true false false 4485000 4485000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 14 -Subparagraph b false 33 Settlements made 1 us-gaap_StandardProductWarrantyAccrualPayments us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false true false false -4191000 -4191000 false false false 4 false true false false -4414000 -4414000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any increase (decrease) in the liability for payments related to extended product warranties Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 14 -Subparagraph b false 34 Accrued warranty liability, balance at end of period 1 us-gaap_StandardProductWarrantyAccrual us-gaap true credit instant No definition available. false false false false false false false false false true false periodendlabel false 1 true true false false 10767000 10767000 false false false 2 true true false false 10347000 10347000 false false false 3 true true false false 10767000 10767000 false false false 4 true true false false 10347000 10347000 false false false 5 false false false false 0 0 false false false 6 false false false false 0 0 false false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false xbrli:monetaryItemType monetary Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 14 -Subparagraph b false 15 30 false NoRounding HundredThousands UnKnown false true