Investments - Schedule of Aggregate Fair Value and Gross Unrealized Loss of Fixed Maturity Securities in an Unrealized Loss Position (Details) $ in Millions	Jun. 30, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	2,726	1,207
Estimated fair value, less than 12 months	$ 9,338	$ 3,594
Gross unrealized loss, less than 12 months	$ (152)	$ (71)
Number of securities, 12 months or greater \| security	2,512	2,946
Estimated fair value, 12 months or greater	$ 3,326	$ 4,208
Gross unrealized loss, 12 months or greater	$ (428)	$ (423)
United States Government securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	47	18
Estimated fair value, less than 12 months	$ 883	$ 460
Gross unrealized loss, less than 12 months	$ (13)	$ (3)
Number of securities, 12 months or greater \| security	13	17
Estimated fair value, 12 months or greater	$ 122	$ 167
Gross unrealized loss, 12 months or greater	$ (16)	$ (16)
Government sponsored securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	12	4
Estimated fair value, less than 12 months	$ 16	$ 0
Gross unrealized loss, less than 12 months	$ 0	$ 0
Number of securities, 12 months or greater \| security	11	16
Estimated fair value, 12 months or greater	$ 9	$ 29
Gross unrealized loss, 12 months or greater	$ 0	$ (1)
Foreign government securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	2	1
Estimated fair value, less than 12 months	$ 7	$ 3
Gross unrealized loss, less than 12 months	$ 0	$ 0
Number of securities, 12 months or greater \| security	1	2
Estimated fair value, 12 months or greater	$ 0	$ 1
Gross unrealized loss, 12 months or greater	$ 0	$ 0
States, municipalities and political subdivisions, tax-exempt
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	246	213
Estimated fair value, less than 12 months	$ 606	$ 486
Gross unrealized loss, less than 12 months	$ (8)	$ (8)
Number of securities, 12 months or greater \| security	360	522
Estimated fair value, 12 months or greater	$ 586	$ 848
Gross unrealized loss, 12 months or greater	$ (52)	$ (66)
Corporate securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	1,565	568
Estimated fair value, less than 12 months	$ 4,705	$ 1,398
Gross unrealized loss, less than 12 months	$ (80)	$ (22)
Number of securities, 12 months or greater \| security	644	839
Estimated fair value, 12 months or greater	$ 1,014	$ 1,397
Gross unrealized loss, 12 months or greater	$ (96)	$ (108)
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	362	169
Estimated fair value, less than 12 months	$ 1,159	$ 282
Gross unrealized loss, less than 12 months	$ (16)	$ (4)
Number of securities, 12 months or greater \| security	1,151	1,164
Estimated fair value, 12 months or greater	$ 905	$ 1,012
Gross unrealized loss, 12 months or greater	$ (139)	$ (132)
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	186	80
Estimated fair value, less than 12 months	$ 810	$ 308
Gross unrealized loss, less than 12 months	$ (10)	$ (6)
Number of securities, 12 months or greater \| security	154	212
Estimated fair value, 12 months or greater	$ 308	$ 479
Gross unrealized loss, 12 months or greater	$ (24)	$ (25)
Other asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	306	154
Estimated fair value, less than 12 months	$ 1,152	$ 657
Gross unrealized loss, less than 12 months	$ (25)	$ (28)
Number of securities, 12 months or greater \| security	178	174
Estimated fair value, 12 months or greater	$ 382	$ 275
Gross unrealized loss, 12 months or greater	$ (101)	$ (75)

Elevance Health, Inc. 10-Q