Consolidated Statements of Changes in Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Net Unrealized (Losses) Gains on Investments [Member]	Foreign Currency Translation Losses [Member]	Noncontrolling Interest
Balance at Dec. 31, 2018	$ 54,319	$ 10	$ 0	$ 55,846	$ (264)	$ (3,896)	$ 2,623
Balance (Accounting Standards Update 2016-02 [Member]) at Dec. 31, 2018	(18)			(13)			(5)
Balance (in shares) at Dec. 31, 2018		960
Net earnings attributable to UnitedHealth Group common shareholders	13,839			13,839
Net earnings attributable to nonredeemable noncontrolling interest							285
Net earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	14,124
Other comprehensive income (loss)	582				853	(271)
Issuances of common stock, and related tax effects (in shares)		10
Issuances of common stock, and related tax effects	696	$ 0	696
Share-based compensation	673		673
Common share repurchases (in shares)		(22)
Common share repurchases	(5,500)	$ (1)	(937)	(4,562)
Cash dividends paid on common shares ($5.60 per share, $4.83 per share and $4.14 per share for the years ended December 31, 2021, 2020 and 2019, respectively)	(3,932)			(3,932)
Redeemable noncontrolling interests fair value and other adjustments	(316)		(316)
Acquisition and other adjustments of nonredeemable noncontrolling interests	87		(109)				196
Distributions to nonredeemable noncontrolling interests	(279)						(279)
Balance at Dec. 31, 2019	60,436	$ 9	7	61,178	589	(4,167)	2,820
Balance (Accounting Standards Update 2016-13) at Dec. 31, 2019	(28)			(28)
Balance (in shares) at Dec. 31, 2019		948
Net earnings attributable to UnitedHealth Group common shareholders	15,403			15,403
Net earnings attributable to nonredeemable noncontrolling interest							254
Net earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	15,657
Other comprehensive income (loss)	(236)				747	(983)
Issuances of common stock, and related tax effects (in shares)		12
Issuances of common stock, and related tax effects	1,120	$ 1	1,119
Share-based compensation	$ 647		647
Common share repurchases (in shares)	(14)	(14)
Common share repurchases	$ (4,250)	$ 0	(1,576)	(2,674)
Cash dividends paid on common shares ($5.60 per share, $4.83 per share and $4.14 per share for the years ended December 31, 2021, 2020 and 2019, respectively)	(4,584)			(4,584)
Redeemable noncontrolling interests fair value and other adjustments	(197)		(197)
Acquisition and other adjustments of nonredeemable noncontrolling interests	40						40
Distributions to nonredeemable noncontrolling interests	(277)						(277)
Balance at Dec. 31, 2020	$ 68,328	$ 10	0	69,295	1,336	(5,150)	2,837
Balance (in shares) at Dec. 31, 2020	946	946
Net earnings attributable to UnitedHealth Group common shareholders	$ 17,285			17,285
Net earnings attributable to nonredeemable noncontrolling interest							360
Net earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	17,645
Other comprehensive income (loss)	(1,570)				(913)	(657)
Issuances of common stock, and related tax effects (in shares)		8
Issuances of common stock, and related tax effects	1,100	$ 0	1,100
Share-based compensation	$ 729		729
Common share repurchases (in shares)	(13)	(13)
Common share repurchases	$ (5,000)	$ 0	(940)	(4,060)
Cash dividends paid on common shares ($5.60 per share, $4.83 per share and $4.14 per share for the years ended December 31, 2021, 2020 and 2019, respectively)	(5,280)			(5,280)
Redeemable noncontrolling interests fair value and other adjustments	(995)		(889)	(106)
Acquisition and other adjustments of nonredeemable noncontrolling interests	407						407
Distributions to nonredeemable noncontrolling interests	(319)						(319)
Balance at Dec. 31, 2021	$ 75,045	$ 10	$ 0	$ 77,134	$ 423	$ (5,807)	$ 3,285
Balance (in shares) at Dec. 31, 2021	941	941