SEGMENT INFORMATION - Schedule of Segment Results (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
External revenues
Premiums revenue	$ 30,711	$ 27,951	$ 91,941	$ 84,354
Services revenue	1,600	1,103	4,334	3,265
Total revenues	32,649	29,397	97,149	88,548
Investment income	338	343	874	929
Operating expenses:
Benefits	27,991	25,120	82,091	75,283
Operating costs	4,085	3,339	11,012	9,529
Depreciation and amortization	173	210	534	631
Total operating expenses	32,249	28,669	93,637	85,443
Income (loss) from operations	400	728	3,512	3,105
Product
External revenues
Premiums revenue	30,711	27,951	91,941	84,354
Service
External revenues
Services revenue	1,600	1,103	4,334	3,265
External Revenues
External revenues
Total revenues	32,311	29,054	96,275	87,619
Operating Segments | Insurance
External revenues
Total revenues	31,189	28,370	93,220	85,594
Investment income	210	192	551	522
Operating expenses:
Benefits	27,982	25,319	82,278	75,752
Operating costs	2,808	2,595	7,900	7,354
Depreciation and amortization	148	182	451	553
Total operating expenses	30,938	28,096	90,629	83,659
Income (loss) from operations	251	274	2,591	1,935
Operating Segments | CenterWell
External revenues
Total revenues	5,879	5,041	16,511	14,806
Investment income	0	0	0	0
Operating expenses:
Benefits	0	0	0	0
Operating costs	5,521	4,602	15,298	13,638
Depreciation and amortization	53	57	172	166
Total operating expenses	5,574	4,659	15,470	13,804
Income (loss) from operations	305	382	1,041	1,002
Operating Segments | Product | Insurance
External revenues
Premiums revenue	30,711	27,951	91,941	84,354
Operating Segments | Product | CenterWell
External revenues
Premiums revenue	0	0	0	0
Operating Segments | Service | Insurance
External revenues
Services revenue	267	226	725	715
Operating Segments | Service | CenterWell
External revenues
Services revenue	1,333	877	3,609	2,550
Operating Segments | External Revenues | Insurance
External revenues
Total revenues	30,978	28,177	92,666	85,069
Operating Segments | External Revenues | CenterWell
External revenues
Total revenues	1,333	877	3,609	2,550
Eliminations/ Corporate
External revenues
Total revenues	(4,419)	(4,014)	(12,582)	(11,852)
Investment income	128	151	323	407
Operating expenses:
Benefits	9	(199)	(187)	(469)
Operating costs	(4,244)	(3,858)	(12,186)	(11,463)
Depreciation and amortization	(28)	(29)	(89)	(88)
Total operating expenses	(4,263)	(4,086)	(12,462)	(12,020)
Income (loss) from operations	(156)	72	(120)	168
Eliminations/ Corporate | Insurance
External revenues
Total revenues	1	1	3	3
Eliminations/ Corporate | CenterWell
External revenues
Total revenues	4,546	4,164	12,902	12,256
Intersegment Eliminations
External revenues
Total revenues	$ (4,547)	$ (4,165)	$ (12,905)	$ (12,259)