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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(b)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(c)
falsefalse11false0unh_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeituresunhfalsenadurationShare-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Forfeituresfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truetruefalse0.050.05falsefalsefalsefalsefalse2truetruefalse0.050.05falsefalsefalsefalsefalse3truetruefalse0.050.05falsefalsefalsefalsefalseOtherus-types:percentItemTypepureShare-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected ForfeituresNo authoritative reference available.falsefalse12false0unh_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermLowerLimitunhfalsenadurationShare-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Lower Limitfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse4.64.6falsefalsefalsefalsefalse2truefalsefalse4.44.4falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:decimalItemTypedecimalShare-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Lower LimitNo authoritative reference available.falsefalse13false0unh_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermUpperLimitunhfalsenadurationShare-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Upper Limitfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse5.15.1falsefalsefalsefalsefalse2truefalsefalse5.15.1falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:decimalItemTypedecimalShare-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Upper LimitNo authoritative reference available.falsefalse14false0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse4.34.3falsefalsefalsefalsefalseOtherxbrli:decimalItemTypedecimalThe period of time a share-based award is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(a)
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section D
-Subsection 2
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