2.2.0.25falsefalse21600 - Disclosure - Business Segment Information (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_BusinessSegmentInformationPoliciesAbstractwatfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseBusiness Segment Information (Policies) [Abstract]3false0wat_SegmentReportingPolicyTextBlockwatfalsenadurationDescribes the entity's policy for segment reporting.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The accounting standard for segment reporting establishes standards for reporting information about operating segments in annual financial statements and requires selected information for those segments to be presented in interim financial reports of public business enterprises. It also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company's business activities, for which discrete financial information is available, are regularly reviewed and evaluated by the chief operating decision makers. As a result of this evaluation, the Company determined that it has two operating segments: Waters Division and TA Division. Waters Division is primarily in the business of designing, manufacturing, distributing and servicing LC and MS instruments, columns and other chemistry consumables that can be integrated and used along with other analytical instruments. TA Division is primarily in the business of designing, manufacturing, distributing and servicing thermal analysis, rheometry and calorimetry instruments. The Company's two divisions are its operating segments and each has similar economic characteristics; product processes; products and services; types and classes of customers; methods of distribution and regulatory environments. Because of these similarities, the two segments have been aggregated into one reporting segment for financial statement purposes.The accounting standard for segment reporting establishes standards for reporting information about operating segments in annual financial statements andfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes the entity's policy for segment reporting.No authoritative reference available.falsefalseSegment Reporting Policy12Business Segment Information (Policies)UnKnownUnKnownUnKnownUnKnownfalsetrue