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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse6605500066055000falsefalsefalsefalsefalse2truefalsefalse131772000131772000falsefalsefalsefalsefalse3truefalsefalse1105500011055000falsefalsefalsetruefalse4truefalsefalse1177200011772000falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15truefalsefalse5500000055000000falsefalsefalsetruefalse16truefalsefalse120000000120000000falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5 falsefalseNotes payable and debt10false0us-gaap_LongTermDebtNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse700000000700000000falsefalsefalsefalsefalse2truefalsefalse500000000500000000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse200000000200000000falsefalsefalsetruefalse6truefalsefalse100000000100000000falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8truefalsefalse100000000100000000falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12truefalsefalse500000000500000000falsefalsefalsetruefalse13truefalsefalse500000000500000000falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 truefalseLong-term debt11false0wat_TotalDebtwatfalsecreditinstantSum of the carrying values as of the balance sheet date of all debt.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse766055000766055000falsefalsefalsefalsefalse2truefalsefalse631772000631772000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying values as of the balance sheet date of all debt.No authoritative reference available.truefalseTotal debt12false0wat_WeightedAverageInterestRatewatfalsenainstantReflects the calculation as of the balance-sheet date of the average interest rate weighted by the amount of total debt...falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00falsefalsefalsefalsefalse2falsetruefalse00falsefalsefalsefalsefalse3truetruefalse0.02100.0210falsefalsefalsetruefalse4truetruefalse0.01970.0197falsefalsefalsetruefalse5falsetruefalse00falsefalsefalsetruefalse6falsetruefalse00falsefalsefalsetruefalse7falsetruefalse00falsefalsefalsetruefalse8falsetruefalse00falsefalsefalsetruefalse9falsetruefalse00falsefalsefalsetruefalse10falsetruefalse00falsefalsefalsetruefalse11falsetruefalse00falsefalsefalsetruefalse12falsetruefalse00falsefalsefalsetruefalse13falsetruefalse00falsefalsefalsetruefalse14falsetruefalse00falsefalsefalsetruefalse15falsetruefalse00falsefalsefalsetruefalse16falsetruefalse00falsefalsefalsetruefalse17falsetruefalse00falsefalsefalsetruefalse18falsetruefalse00falsefalsefalsetruefalse19falsetruefalse00falsefalsefalsetruefalse20truetruefalse0.01690.0169falsefalsefalsetruefalse21truetruefalse0.00780.0078falsefalsefalsetruefalseOtherus-types:percentItemTypepureReflects 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.No authoritative reference available.falsefalseWeighted-average interest rate13false0us-gaap_DebtInstrumentUnusedBorrowingCapacityAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10truefalsefalse543000000543000000falsefalsefalsetruefalse11truefalsefalse479000000479000000falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance-sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Subparagraph b -Article 5 falsefalseUnused borrowing capacity14false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse111000000111000000falsetruefalsetruefalse4truefalsefalse8800000088000000falsetruefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseLine of credit maximum borrowing capacity2113Debt (Details) (USD $)NoRoundingUnKnownUnKnownUnKnowntruetrue