2.2.0.25falsefalse006001 - Disclosure - Nature of Businesstruefalsefalse1falsefalseUSDfalsefalse1/1/2011 - 3/31/2011 USD ($) $FROM_Jan01_2011_TO_Mar31_2011http://www.sec.gov/CIK0001289592duration2011-01-01T00:00:002011-03-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0twgp_NatureOfBusinessAbstracttwgpfalsenadurationNature of Business.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNature of Business.falsefalseNature of Business [Abstract]3false0us-gaap_NatureOfOperationsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Note 1—Nature of BusinessTower Group, Inc. (the “Company” or “Tower”), through its subsidiaries, offers a broad range of commercial, personal and specialty property and casualty insurance products and services to businesses in various industries and to individuals. The Company's common stock is publicly traded on the NASDAQ Global Select Market under the symbol “TWGP”.The Company operates three business segments: Commercial Insurance, Personal Insurance and Insurance Services:<ul><li style="margin-left:36px;list-style:disc;">Commercial Insurance (“Commercial”) Segment offers a broad range of general and specialty commercial lines property and casualty insurance products to businesses distributed through a network of retail and wholesale agents and program underwriting agents on both an admitted and non-admitted basis. This segment also includes assumed reinsurance; </li><li style="margin-left:36px;list-style:disc;">Personal Insurance (“Personal”) Segment offers a broad range of personal lines property and casualty insurance products to individuals distributed through a network of retail and wholesale agents; and</li><li style="margin-left:36px;list-style:disc;">Insurance Services (“Services”) Segment provides underwriting, claims and reinsurance brokerage services to insurance companies.</li></ul>Note 1—Nature of BusinessTower Group, Inc. (the “Company” or “Tower”), through its subsidiaries, offers a broad range offalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes the nature of an entity's business, the major products or services it sells or provides and its principal markets, including the locations of those markets. If the entity operates in more than one business, the disclosure also indicates the relative importance of its operations in each business and the basis for the determination (for example, assets, revenues, or earnings). Disclosures about the nature of operations need not be quantified; relative importance could be conveyed by use of terms such as "predominately", "about equally", or "major and other". This element is also referred to as "Business Description".Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-6 -Paragraph 10 falsefalseNature of Business12Nature of BusinessUnKnownUnKnownUnKnownUnKnownfalsetrue