2.2.0.25truefalse41201 - Disclosure - AARP (Narrative) (Details)truefalseIn Millionsfalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010
USD ($)
USD ($) / shares
$Duration_1_1_2010_To_12_31_2010http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse1/1/2009 - 12/31/2009
USD ($)
USD ($) / shares
$Duration_1_1_2009_To_12_31_20092http://www.sec.gov/CIK0000731766duration2009-01-01T00:00:002009-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$3falsefalseUSDfalsefalse1/1/2008 - 12/31/2008
USD ($)
USD ($) / shares
$Duration_1_1_2008_To_12_31_20082http://www.sec.gov/CIK0000731766duration2008-01-01T00:00:002008-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2false0us-gaap_PremiumsEarnedNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse8540500000085405falsetruefalsefalsefalse2truefalsefalse7931500000079315falsetruefalsefalsefalse3truefalsefalse7360800000073608falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryPremiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 1
-Article 7
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 113
-Paragraph 27
-Subparagraph a, b
falsefalse3false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.unitedhealthgroup.com/taxonomy/role/disclosureaarpnarrativedetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse4falsefalseUSDtruefalse{us-gaap_SupplementaryInsuranceInformationSegmentNameAxis} : AARP Program
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_20103http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseAARP Programus-gaap_SupplementaryInsuranceInformationSegmentNameAxisxbrldihttp://xbrl.org/2006/xbrldiunh_AARPProgramMemberus-gaap_SupplementaryInsuranceInformationSegmentNameAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5falsefalseUSDtruefalse{us-gaap_SupplementaryInsuranceInformationSegmentNameAxis} : AARP Program
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200922http://www.sec.gov/CIK0000731766duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseAARP Programus-gaap_SupplementaryInsuranceInformationSegmentNameAxisxbrldihttp://xbrl.org/2006/xbrldiunh_AARPProgramMemberus-gaap_SupplementaryInsuranceInformationSegmentNameAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falsefalseUSDtruefalse{us-gaap_SupplementaryInsuranceInformationSegmentNameAxis} : AARP Program
1/1/2008 - 12/31/2008
USD ($)
$Duration_1_1_2008_To_12_31_20083http://www.sec.gov/CIK0000731766duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseAARP Programus-gaap_SupplementaryInsuranceInformationSegmentNameAxisxbrldihttp://xbrl.org/2006/xbrldiunh_AARPProgramMemberus-gaap_SupplementaryInsuranceInformationSegmentNameAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse4false0us-gaap_PremiumsEarnedNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse63000000006300falsefalsefalsefalsefalse2truefalsefalse60000000006000falsefalsefalsefalsefalse3truefalsefalse57000000005700falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryPremiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 1
-Article 7
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 113
-Paragraph 27
-Subparagraph a, b
falsefalse5false0unh_InterestIncomeAndRealizedGainsLossesRelatedToAssetsUnderManagementunhfalsecreditdurationInterest income and realized gains and losses related to assets under management recorded as an increase to the AARP Rate...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse107000000107falsetruefalsefalsefalse2truefalsefalse9900000099falsetruefalsefalsefalse3truefalsefalse8200000082falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryInterest income and realized gains and losses related to assets under management recorded as an increase to the AARP Rate Stabilization Fund.No authoritative reference available.falsefalse34AARP (Narrative) (Details) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
