2.2.0.7 false Shareholders' Equity (Narrative) (Details) (USD $) 40901 - Disclosure - Shareholders' Equity (Narrative) (Details) true false In Millions, except Per Share data false false 1 USD false false Unit13 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Standard http://www.xbrl.org/2003/instance pure xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 false false Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 5 3 unh_AdditionalSharesAuthorizedForRepurchase unh false na instant Additional shares authorized for repurchase false false false false false false false false false false false terselabel false 1 false true false false 65000000 65 false false false 2 false true false false 120000000 120 false false false xbrli:sharesItemType shares Additional shares authorized for repurchase No authoritative reference available. false 6 3 us-gaap_StockRepurchasedDuringPeriodShares us-gaap true na duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 59000000 59 false false false 2 false false false false 0 0 false false false xbrli:sharesItemType shares Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 1 -Section B -Paragraph 11A false 7 3 unh_AverageSharePriceForCommonStockRepurchases unh false na duration Average share price for common stock repurchases. false false false false false false false false false false false terselabel true 1 true true false false 32 32 false false false 2 false false false false 0 0 false false false us-types:perShareItemType decimal Average share price for common stock repurchases. No authoritative reference available. false 8 3 us-gaap_StockRepurchasedDuringPeriodValue us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 true true false false 1892000000 1892 false false false 2 false false false false 0 0 false false false xbrli:monetaryItemType monetary This element represents the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 1 -Section B -Paragraph 11A false 2 4 false Millions Millions NoRounding false true