Held for Sale and Dispositions (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Held for Sale and Dispositions [Line Items]
Cash received from dispositions and other strategic transactions, net	$ 1,081	$ 21
United Health Foundation contribution
Held for Sale and Dispositions [Line Items]
Restructuring Costs	400
Optum Health
Held for Sale and Dispositions [Line Items]
Restructuring Costs	135
Incremental loss on disposition of business	314
Optum Insight
Held for Sale and Dispositions [Line Items]
Gain on disposition of business	525
Restructuring Costs	339
Other Businesses, Held-for-Sale, Not Discontinued Operations
Held for Sale and Dispositions [Line Items]
Total assets	1,021
Total liabilities	807
Disposition
Held for Sale and Dispositions [Line Items]
Cash received from dispositions and other strategic transactions, net	1,100
Total assets	1,200
Total liabilities	442
Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)	160
Gain on disposition of business	$ 211

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