Investments - Investments by Category, Including Disposal Groups (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Current
Investments including held for sale assets		$ 748
Current investments	$ 883	665
Long-term
Investments including held for sale assets		16,489
Investments per Consolidated Balance Sheets	18,483	15,128
Total
Investments including held for sale assets		17,237
Total investments	19,366	15,793
Held-for-Sale \| Medicare Advantage and related Cigna Healthcare businesses
Current
Investments classified as assets of business held for sale		(83)
Long-term
Investments classified as assets of business held for sale		(1,361)
Total
Investments classified as assets of business held for sale		(1,444)
Debt securities
Current
Investments including held for sale assets		463
Current investments	490
Long-term
Investments including held for sale assets		8,960
Investments per Consolidated Balance Sheets	7,861
Total
Investments including held for sale assets		9,423
Total investments	8,351
Equity securities
Current
Investments including held for sale assets		7
Current investments	17
Long-term
Investments including held for sale assets		554
Investments per Consolidated Balance Sheets	3,500
Total
Investments including held for sale assets		561
Total investments	3,517
Commercial mortgage loans
Current
Investments including held for sale assets		108
Current investments	100
Long-term
Investments including held for sale assets		1,243
Investments per Consolidated Balance Sheets	1,158
Total
Investments including held for sale assets		1,351
Total investments	1,258
Policy loans
Current
Investments including held for sale assets		0
Current investments	0
Long-term
Investments including held for sale assets		1,156
Investments per Consolidated Balance Sheets	1,080
Total
Investments including held for sale assets		1,156
Total investments	1,080
Other long-term investments
Current
Investments including held for sale assets		0
Current investments	0
Long-term
Investments including held for sale assets		4,576
Investments per Consolidated Balance Sheets	4,884
Total
Investments including held for sale assets		4,576
Total investments	4,884
Short-term investments
Current
Investments including held for sale assets		170
Current investments	276
Long-term
Investments including held for sale assets		0
Investments per Consolidated Balance Sheets	0
Total
Investments including held for sale assets		$ 170
Total investments	$ 276

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