2.2.0.25truefalse40801 - Disclosure - Commercial Paper and Long-Term Debt (Narrative) (Details)truefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 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$2falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : Due October 2020
{us-gaap_DebtInstrumentAxis} : Senior Unsecured Notes
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103253http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseDue October 2020us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueOctober2020Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseSenior Unsecured Notesus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredNotesMemberus-gaap_DebtInstrumentAxisexplicitMember3falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : Due October 2020
{us-gaap_DebtInstrumentAxis} : Senior Unsecured Notes
10/25/2010
USD ($)
$As_Of_10_25_20103http://www.sec.gov/CIK0000731766instant2010-10-25T00:00:000001-01-01T00:00:00falsefalseDue October 2020us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueOctober2020Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseSenior Unsecured Notesus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredNotesMemberus-gaap_DebtInstrumentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : Due October 2020
{unh_RangeAxis} : Fixed Rate 3.875 Percent
10/25/2010
USD ($)
$As_Of_10_25_2010http://www.sec.gov/CIK0000731766instant2010-10-25T00:00:000001-01-01T00:00:00falsefalseDue October 2020us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueOctober2020Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 3.875 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRate3875PercentMemberunh_RangeAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$5falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : Due October 2040
{us-gaap_DebtInstrumentAxis} : Senior Unsecured Notes
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103254http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseDue October 2040us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueOctober2040Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseSenior Unsecured Notesus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredNotesMemberus-gaap_DebtInstrumentAxisexplicitMember6falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : Due October 2040
{unh_RangeAxis} : Fixed Rate 5.700 Percent
10/25/2010
USD ($)
$As_Of_10_25_20102http://www.sec.gov/CIK0000731766instant2010-10-25T00:00:000001-01-01T00:00:00falsefalseDue October 2040us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueOctober2040Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 5.700 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRate5700PercentMemberunh_RangeAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$7falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : Due February 2018
{unh_RangeAxis} : Fixed Rate 6.0 Percent
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_2010325http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseDue February 2018us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueFebruary2018Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 6.0 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRateSixPercentMemberunh_RangeAxisexplicitMember8falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : Due February 2018
{unh_RangeAxis} : Fixed Rate 6.0 Percent
2/29/2008
USD ($)
$As_Of_2_29_20082http://www.sec.gov/CIK0000731766instant2008-02-29T00:00:000001-01-01T00:00:00falsefalseDue February 2018us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueFebruary2018Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 6.0 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRateSixPercentMemberunh_RangeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$9falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : Due February 2013
{unh_RangeAxis} : Fixed Rate 4.9 Percent
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103233http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseDue February 2013us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueFebruary2013Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 4.9 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRateFourPointNinePercentMemberunh_RangeAxisexplicitMember10falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : Due February 2013
{unh_RangeAxis} : Fixed Rate 4.9 Percent
2/29/2008
USD ($)
$As_Of_2_29_2008http://www.sec.gov/CIK0000731766instant2008-02-29T00:00:000001-01-01T00:00:00falsefalseDue February 2013us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueFebruary2013Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 4.9 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRateFourPointNinePercentMemberunh_RangeAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$11falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : Due February 2038
{unh_RangeAxis} : Fixed Rate 6.9 Percent
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103252http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseDue February 2038us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueFebruary2038Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 6.9 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRateSixPointNinePercentMemberunh_RangeAxisexplicitMember12falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : Due February 2038
{unh_RangeAxis} : Fixed Rate 6.9 Percent
2/29/2008
USD ($)
$As_Of_2_29_20083http://www.sec.gov/CIK0000731766instant2008-02-29T00:00:000001-01-01T00:00:00falsefalseDue February 2038us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_DueFebruary2038Memberus-gaap_LongtermDebtTypeAxisexplicitMemberfalsefalseFixed Rate 6.9 Percentunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_FixedRateSixPointNinePercentMemberunh_RangeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$13falsefalsetruefalse{us-gaap_DebtInstrumentAxis} : Commercial paper
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20104http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseCommercial paperus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialPaperMemberus-gaap_DebtInstrumentAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli014falsefalseUSDtruefalse{us-gaap_DebtInstrumentAxis} : Revolving Credit Facility
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103223http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseRevolving Credit Facilityus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_RevolvingCreditFacilityMemberus-gaap_DebtInstrumentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0$15falsefalsetruefalse{us-gaap_DebtInstrumentAxis} : Revolving Credit Facility
{unh_RangeAxis} : Minimum
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_2010324http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseRevolving Credit Facilityus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_RevolvingCreditFacilityMemberus-gaap_DebtInstrumentAxisexplicitMemberfalsefalseMinimumunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_MinimumMemberunh_RangeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli016falsefalsetruefalse{us-gaap_DebtInstrumentAxis} : Revolving Credit Facility
{unh_RangeAxis} : Maximum
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_2010323http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseRevolving Credit Facilityus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_RevolvingCreditFacilityMemberus-gaap_DebtInstrumentAxisexplicitMemberfalsefalseMaximumunh_RangeAxisxbrldihttp://xbrl.org/2006/xbrldiunh_MaximumMemberunh_RangeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli017falsefalsetruefalse{us-gaap_DebtInstrumentAxis} : Senior Unsecured Notes
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103222http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseSenior Unsecured Notesus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredNotesMemberus-gaap_DebtInstrumentAxisexplicitMember18falsefalseUSDtruefalse{us-gaap_DebtInstrumentAxis} : Senior Unsecured Notes
2/5/2010
USD ($)
$As_Of_2_5_2010http://www.sec.gov/CIK0000731766instant2010-02-05T00:00:000001-01-01T00:00:00falsefalseSenior Unsecured Notesus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredNotesMemberus-gaap_DebtInstrumentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$19falsefalseUSDtruefalse{us-gaap_DebtInstrumentAxis} : Senior Unsecured Notes
2/29/2008
USD ($)
$As_Of_2_29_20085http://www.sec.gov/CIK0000731766instant2008-02-29T00:00:000001-01-01T00:00:00falsefalseSenior Unsecured Notesus-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredNotesMemberus-gaap_DebtInstrumentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$20falsefalsetruefalse{us-gaap_DebtInstrumentAxis} : Senior Unsecured Floating-rate Notes Due February 2011
1/1/2010 - 12/31/2010
Duration_1_1_2010_To_12_31_20103232http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseSenior Unsecured Floating-rate Notes Due February 2011us-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredFloatingRateNotesDueFebruary2011Memberus-gaap_DebtInstrumentAxisexplicitMember21falsefalseUSDtruefalse{us-gaap_DebtInstrumentAxis} : Senior Unsecured Floating-rate Notes Due February 2011
2/29/2008
USD ($)
$As_Of_2_29_20084http://www.sec.gov/CIK0000731766instant2008-02-29T00:00:000001-01-01T00:00:00falsefalseSenior Unsecured Floating-rate Notes Due February 2011us-gaap_DebtInstrumentAxisxbrldihttp://xbrl.org/2006/xbrldiunh_SeniorUnsecuredFloatingRateNotesDueFebruary2011Memberus-gaap_DebtInstrumentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false0unh_MaturityDateOfCommercialPaperunhfalsenadurationMaturity date of commercial paperfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00270270falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringMaturity date of commercial paperNo authoritative reference available.falsefalse3false0us-gaap_DebtInstrumentInterestRateDuringPeriodus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00falsefalsefalsefalsefalse2falsetruefalse00falsefalsefalsetruefalse3falsetruefalse00falsefalsefalsetruefalse4falsetruefalse00falsefalsefalsetruefalse5falsetruefalse00falsefalsefalsetruefalse6falsetruefalse00falsefalsefalsetruefalse7falsetruefalse00falsefalsefalsetruefalse8falsetruefalse00falsefalsefalsetruefalse9falsetruefalse00falsefalsefalsetruefalse10falsetruefalse00falsefalsefalsetruefalse11falsetruefalse00falsefalsefalsetruefalse12falsetruefalse00falsefalsefalsetruefalse13truetruefalse0.0040.004falsefalsefalsetruefalse14falsetruefalse00falsefalsefalsetruefalse15truetruefalse0.0050.005falsefalsefalsetruefalse16truetruefalse0.0070.007falsefalsefalsetruefalse17falsetruefalse00falsefalsefalsetruefalse18falsetruefalse00falsefalsefalsetruefalse19falsetruefalse00falsefalsefalsetruefalse20falsetruefalse00falsefalsefalsetruefalse21falsetruefalse00falsefalsefalsetruefalseOtherus-types:percentItemTypepureThe average effective interest rate during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5
falsefalse4false0us-gaap_LineOfCreditFacilityCurrentBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14truefalsefalse25000000002500000000falsetruefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5
falsefalse5false0unh_MaximumPercentageOfIndebtednessToTotalNetCapitalBankCovenantunhfalsenainstantMaximum percentage of indebtedness to total net capital bank covenantfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsetruefalse00falsefalsefalsefalsefalse2falsetruefalse00falsefalsefalsetruefalse3falsetruefalse00falsefalsefalsetruefalse4falsetruefalse00falsefalsefalsetruefalse5falsetruefalse00falsefalsefalsetruefalse6falsetruefalse00falsefalsefalsetruefalse7falsetruefalse00falsefalsefalsetruefalse8falsetruefalse00falsefalsefalsetruefalse9falsetruefalse00falsefalsefalsetruefalse10falsetruefalse00falsefalsefalsetruefalse11falsetruefalse00falsefalsefalsetruefalse12falsetruefalse00falsefalsefalsetruefalse13falsetruefalse00falsefalsefalsetruefalse14truetruefalse0.50.5falsefalsefalsetruefalse15falsetruefalse00falsefalsefalsetruefalse16falsetruefalse00falsefalsefalsetruefalse17falsetruefalse00falsefalsefalsetruefalse18falsetruefalse00falsefalsefalsetruefalse19falsetruefalse00falsefalsefalsetruefalse20falsetruefalse00falsefalsefalsetruefalse21falsetruefalse00falsefalsefalsetruefalseOtherus-types:percentItemTypepureMaximum percentage of indebtedness to total net capital bank covenantNo authoritative reference available.falsefalse6false0unh_NumberOfBanksunhfalsenainstantNumber of Banksfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14truefalsefalse2323falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:integerItemTypeintegerNumber of BanksNo authoritative reference available.falsefalse7false0us-gaap_LineOfCreditFacilityAmountOutstandingus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14truefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAmount borrowed under the credit facility 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 19, 22
-Article 5
falsefalse8false0unh_DebtInstrumentFaceAmountCashTenderPurchaseunhfalsecreditinstantDebt Instrument, Face Amount, Cash Tender Purchasefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18truefalsefalse775000000775000000falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryDebt Instrument, Face Amount, Cash Tender PurchaseNo authoritative reference available.falsefalse9false0us-gaap_DebtInstrumentInterestRateStatedPercentageus-gaaptruenainstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00falsefalsefalsefalsefalse2falsetruefalse00falsefalsefalsetruefalse3falsetruefalse00falsefalsefalsetruefalse4truetruefalse0.038750.03875falsefalsefalsetruefalse5falsetruefalse00falsefalsefalsetruefalse6truetruefalse0.0570.057falsefalsefalsetruefalse7falsetruefalse00falsefalsefalsetruefalse8truetruefalse0.060.06falsefalsefalsetruefalse9falsetruefalse00falsefalsefalsetruefalse10truetruefalse0.0490.049falsefalsefalsetruefalse11falsetruefalse00falsefalsefalsetruefalse12truetruefalse0.0690.069falsefalsefalsetruefalse13falsetruefalse00falsefalsefalsetruefalse14falsetruefalse00falsefalsefalsetruefalse15falsetruefalse00falsefalsefalsetruefalse16falsetruefalse00falsefalsefalsetruefalse17falsetruefalse00falsefalsefalsetruefalse18falsetruefalse00falsefalsefalsetruefalse19falsetruefalse00falsefalsefalsetruefalse20falsetruefalse00falsefalsefalsetruefalse21falsetruefalse00falsefalsefalsetruefalseOtherus-types:percentItemTypepureInterest rate stated in the contractual debt agreement.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5
falsefalse10false0us-gaap_DebtInstrumentIssuanceDateus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse002/15/20082/15/2008falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19falsefalsefalse00falsefalsefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21falsefalsefalse00falsefalsefalsetruefalseOtherus-types:dateStringItemTypenormalizedstringDate when the debt instrument was issued, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5
falsefalse11false0us-gaap_SeniorNotesus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse750000000750000000falsetruefalsetruefalse4truefalsefalse450000000450000000falsetruefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6truefalsefalse300000000300000000falsetruefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8truefalsefalse11000000001100000000falsetruefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10truefalsefalse550000000550000000falsetruefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12truefalsefalse11000000001100000000falsetruefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18falsefalsefalse00falsefalsefalsetruefalse19truefalsefalse30000000003000000000falsetruefalsetruefalse20falsefalsefalse00falsefalsefalsetruefalse21truefalsefalse250000000250000000falsetruefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryIncluding the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9
falsefalse12false0us-gaap_DebtInstrumentMaturityDateus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsetruefalsefalse2falsefalsefalse002020-10-152020-10-15falsefalsetruetruefalse3falsefalsefalse00falsefalsetruetruefalse4falsefalsefalse00falsefalsetruetruefalse5falsefalsefalse002040-10-152040-10-15falsefalsetruetruefalse6falsefalsefalse00falsefalsetruetruefalse7falsefalsefalse002018-02-152018-02-15falsefalsetruetruefalse8falsefalsefalse00falsefalsetruetruefalse9falsefalsefalse002013-02-152013-02-15falsefalsetruetruefalse10falsefalsefalse00falsefalsetruetruefalse11falsefalsefalse002038-02-152038-02-15falsefalsetruetruefalse12falsefalsefalse00falsefalsetruetruefalse13falsefalsefalse00falsefalsetruetruefalse14falsefalsefalse002012-05-152012-05-15falsefalsetruetruefalse15falsefalsefalse00falsefalsetruetruefalse16falsefalsefalse00falsefalsetruetruefalse17falsefalsefalse00falsefalsetruetruefalse18falsefalsefalse00falsefalsetruetruefalse19falsefalsefalse00falsefalsetruetruefalse20falsefalsefalse002011-02-152011-02-15falsefalsetruetruefalse21falsefalsefalse00falsefalsetruetruefalseOtherxbrli:dateItemTypedateDate when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 4
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