Document and Entity Information Document - USD ($)	12 Months Ended
	Dec. 31, 2017	Jan. 31, 2018	Jun. 30, 2017
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Entitiy Registrant Name	UNITEDHEALTH GROUP INC
Entitiy Central Index Key	0000731766
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Well known seasoned issuer	Yes
Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Common Stock, Shares Outstanding		967,662,919
Closing Share Price			$ 185.42
Public Float			$ 177,882,211,144