2.2.0.25falsefalse20900 - Disclosure - Income Taxes (Policies)truefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $FROM_Jan01_2010_TO_Dec31_2010http://www.sec.gov/CIK0001000697duration2010-01-01T00:00:002010-12-31T00:00:00SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170EPSDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2true0wat_IncomeTaxesPoliciesAbstractwatfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseIncome Taxes (Policies) [Abstract]3false0wat_UncertainIncomeTaxReportingPositionsPolicyTextBlockwatfalsenadurationDescribes an entity's accounting policy for tax positions taken in the Company's tax return filed or to be filed for which it...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:10pt;margin-left:0px;">The Company accounts for its uncertain tax return reporting positions in accordance with the accounting standards for income taxes, which require financial statement reporting of the expected future tax consequences of those tax reporting positions on the presumption that all concerned tax authorities possess full knowledge of those tax reporting positions, as well as all of the pertinent facts and circumstances, but prohibit any discounting of those unrecognized tax benefits for the time value of money.</font></p>The Company accounts for its uncertain tax return reporting positions in accordance with the accounting standards for income taxes, which require financialfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes 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.No authoritative reference available.falsefalseUncertain Income Tax Reporting Positions Policy12Income Taxes (Policies)UnKnownUnKnownUnKnownUnKnownfalsetrue