Investments - Investments by Category (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current
Investments including held for sale assets	$ 1,193	$ 1,009
Current investments	1,108	925
Long-term
Investments including held for sale assets	17,281	19,339
Investments per Consolidated Balance Sheets	16,025	17,985
Total
Investments including held for sale assets	18,474	20,348
Total investments	17,133	18,910
Held-for-Sale \| Medicare Advantage and related Cigna Healthcare businesses
Current
Investments classified as assets of business held for sale	(85)	(84)
Long-term
Investments classified as assets of business held for sale	(1,256)	(1,354)
Total
Investments classified as assets of business held for sale	(1,341)	(1,438)
Debt securities
Current
Investments including held for sale assets	604	590
Long-term
Investments including held for sale assets	8,876	9,265
Total
Investments including held for sale assets	9,480	9,855
Equity securities
Current
Investments including held for sale assets	18	31
Long-term
Investments including held for sale assets	1,553	3,331
Total
Investments including held for sale assets	1,571	3,362
Commercial mortgage loans
Current
Investments including held for sale assets	197	182
Long-term
Investments including held for sale assets	1,365	1,351
Total
Investments including held for sale assets	1,562	1,533
Policy loans
Current
Investments including held for sale assets	0	0
Long-term
Investments including held for sale assets	1,186	1,211
Total
Investments including held for sale assets	1,186	1,211
Other long-term investments
Current
Investments including held for sale assets	0	0
Long-term
Investments including held for sale assets	4,301	4,181
Total
Investments including held for sale assets	4,301	4,181
Short-term investments
Current
Investments including held for sale assets	374	206
Long-term
Investments including held for sale assets	0	0
Total
Investments including held for sale assets	$ 374	$ 206

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