SEGMENT INFORMATION - Segment Results (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Premiums	$ 87,712	$ 79,822	$ 74,186
Services revenue	4,776	3,055	1,815
Total revenues	92,870	83,064	77,155
Investment income	382	187	1,154
Benefits	75,690	69,199	61,628
Operating costs	12,671	10,121	10,052
Depreciation and amortization	709	596	489
Total operating expenses	89,070	79,916	72,169
Income from operations	3,800	3,148	4,986
Gain on sale of KAH Hospice	(237)	0	0
Interest expense	401	326	283
Other expense (income), net	68	(532)	103
Income before income taxes and equity in net (losses) earnings	3,568	3,354	4,600
Equity in net (losses) earnings	(4)	65	74
Segment earnings	3,564	3,419	4,674
Net (income) loss attributable to noncontrolling interests	4	(1)
Segment earnings (loss) attributable to Humana	3,568	3,418
Individual Medicare Advantage
Segment Reporting Information [Line Items]
Premiums	65,591	58,654	51,697
Group Medicare Advantage
Segment Reporting Information [Line Items]
Premiums	7,297	6,955	7,774
Medicare stand-alone PDP
Segment Reporting Information [Line Items]
Premiums	2,269	2,371	2,742
Total Medicare
Segment Reporting Information [Line Items]
Premiums	75,157	67,980	62,213
Fully-insured
Segment Reporting Information [Line Items]
Premiums	4,476	5,002	6,051
Specialty
Segment Reporting Information [Line Items]
Premiums	1,703	1,731	1,699
Medicaid and other
Segment Reporting Information [Line Items]
Premiums	6,376	5,109	4,223
Home solutions
Segment Reporting Information [Line Items]
Services revenue	2,333	1,166	107
Provider
Segment Reporting Information [Line Items]
Services revenue	568	413	328
ASO and other
Segment Reporting Information [Line Items]
Services revenue	850	853	813
Pharmacy
Segment Reporting Information [Line Items]
Services revenue	1,025	623	567
Insurance
Segment Reporting Information [Line Items]
Total revenues	88,841	80,930	74,597
Investment income	223	214	171
Total operating expenses	85,819	78,518	71,477
CenterWell
Segment Reporting Information [Line Items]
Total revenues	17,307	14,058	11,490
Investment income	8	4	13
Total operating expenses	16,016	13,120	10,866
Operating Segments
Segment Reporting Information [Line Items]
Total revenues	92,488	82,877	76,001
Operating Segments | Insurance
Segment Reporting Information [Line Items]
Premiums	87,712	79,822	73,584
Services revenue	850	853	813
Total revenues	88,562	80,675	74,397
Benefits	75,934	69,639	61,909
Operating costs	9,251	8,340	9,129
Depreciation and amortization	634	539	439
Income from operations	3,022	2,412	3,120
Gain on sale of KAH Hospice	0
Interest expense	0	0	0
Other expense (income), net	0	0	0
Income before income taxes and equity in net (losses) earnings	3,022	2,412	3,120
Equity in net (losses) earnings	18	0	0
Segment earnings	3,040	2,412	3,120
Net (income) loss attributable to noncontrolling interests	5	0
Segment earnings (loss) attributable to Humana	3,045	2,412
Operating Segments | Insurance | Individual Medicare Advantage
Segment Reporting Information [Line Items]
Premiums	65,591	58,654	51,697
Operating Segments | Insurance | Group Medicare Advantage
Segment Reporting Information [Line Items]
Premiums	7,297	6,955	7,774
Operating Segments | Insurance | Medicare stand-alone PDP
Segment Reporting Information [Line Items]
Premiums	2,269	2,371	2,742
Operating Segments | Insurance | Total Medicare
Segment Reporting Information [Line Items]
Premiums	75,157	67,980	62,213
Operating Segments | Insurance | Fully-insured
Segment Reporting Information [Line Items]
Premiums	4,476	5,002	5,449
Operating Segments | Insurance | Specialty
Segment Reporting Information [Line Items]
Premiums	1,703	1,731	1,699
Operating Segments | Insurance | Medicaid and other
Segment Reporting Information [Line Items]
Premiums	6,376	5,109	4,223
Operating Segments | Insurance | Home solutions
Segment Reporting Information [Line Items]
Services revenue	0	0	0
Operating Segments | Insurance | Provider
Segment Reporting Information [Line Items]
Services revenue	0	0	0
Operating Segments | Insurance | ASO and other
Segment Reporting Information [Line Items]
Services revenue	850	853	813
Operating Segments | Insurance | Pharmacy
Segment Reporting Information [Line Items]
Services revenue	0	0	0
Operating Segments | CenterWell
Segment Reporting Information [Line Items]
Premiums	0	0	0
Services revenue	3,926	2,202	1,002
Total revenues	3,926	2,202	1,002
Benefits	0	0	0
Operating costs	15,835	12,968	10,706
Depreciation and amortization	181	152	160
Income from operations	1,291	938	624
Gain on sale of KAH Hospice	(237)
Interest expense	0	0	0
Other expense (income), net	0	0	0
Income before income taxes and equity in net (losses) earnings	1,528	938	624
Equity in net (losses) earnings	(22)	65	74
Segment earnings	1,506	1,003	698
Net (income) loss attributable to noncontrolling interests	(1)	(1)
Segment earnings (loss) attributable to Humana	1,505	1,002
Operating Segments | CenterWell | Individual Medicare Advantage
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Group Medicare Advantage
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Medicare stand-alone PDP
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Total Medicare
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Fully-insured
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Specialty
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Medicaid and other
Segment Reporting Information [Line Items]
Premiums	0	0	0
Operating Segments | CenterWell | Home solutions
Segment Reporting Information [Line Items]
Services revenue	2,333	1,166	107
Operating Segments | CenterWell | Provider
Segment Reporting Information [Line Items]
Services revenue	568	413	328
Operating Segments | CenterWell | ASO and other
Segment Reporting Information [Line Items]
Services revenue	0	0	0
Operating Segments | CenterWell | Pharmacy
Segment Reporting Information [Line Items]
Services revenue	1,025	623	567
Eliminations/ Corporate
Segment Reporting Information [Line Items]
Premiums			602
Total revenues	(13,278)	(11,924)	(8,932)
Investment income	151	(31)	970
Benefits	(244)	(440)	(281)
Operating costs	(12,415)	(11,187)	(9,783)
Depreciation and amortization	(106)	(95)	(110)
Total operating expenses	(12,765)	(11,722)	(10,174)
Income from operations	(513)	(202)	1,242
Gain on sale of KAH Hospice	0
Interest expense	401	326	283
Other expense (income), net	68	(532)	103
Income before income taxes and equity in net (losses) earnings	(982)	4	856
Equity in net (losses) earnings	0	0	0
Segment earnings	(982)	4	856
Net (income) loss attributable to noncontrolling interests	0	0
Segment earnings (loss) attributable to Humana	(982)	4
Eliminations/ Corporate | Fully-insured
Segment Reporting Information [Line Items]
Premiums			602
Total revenues			602
Eliminations/ Corporate | Insurance
Segment Reporting Information [Line Items]
Total revenues	56	41	29
Eliminations/ Corporate | Insurance | Services
Segment Reporting Information [Line Items]
Total revenues	56	41	29
Eliminations/ Corporate | Insurance | Products
Segment Reporting Information [Line Items]
Total revenues	0	0	0
Eliminations/ Corporate | CenterWell
Segment Reporting Information [Line Items]
Total revenues	13,373	11,852	10,475
Eliminations/ Corporate | CenterWell | Services
Segment Reporting Information [Line Items]
Total revenues	3,532	2,828	2,547
Eliminations/ Corporate | CenterWell | Products
Segment Reporting Information [Line Items]
Total revenues	9,841	9,024	7,928
Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues	(13,429)	(11,893)	(10,504)
Intersegment Eliminations | Services
Segment Reporting Information [Line Items]
Total revenues	(3,588)	(2,869)	(2,576)
Intersegment Eliminations | Products
Segment Reporting Information [Line Items]
Total revenues	$ (9,841)	$ (9,024)	$ (7,928)