Investments - Investments by Category, Including Disposal Groups (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Current
Investments including held for sale assets		$ 748
Current investments	$ 727	665
Long-term
Investments including held for sale assets		16,489
Investments per Consolidated Balance Sheets	15,350	15,128
Total
Investments including held for sale assets		17,237
Total investments	16,077	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	454
Long-term
Investments including held for sale assets		8,960
Investments per Consolidated Balance Sheets	7,761
Total
Investments including held for sale assets		9,423
Total investments	8,215
Equity securities
Current
Investments including held for sale assets		7
Current investments	11
Long-term
Investments including held for sale assets		554
Investments per Consolidated Balance Sheets	548
Total
Investments including held for sale assets		561
Total investments	559
Commercial mortgage loans
Current
Investments including held for sale assets		108
Current investments	66
Long-term
Investments including held for sale assets		1,243
Investments per Consolidated Balance Sheets	1,228
Total
Investments including held for sale assets		1,351
Total investments	1,294
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	1,128
Total
Investments including held for sale assets		1,156
Total investments	1,128
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	4,685
Total
Investments including held for sale assets		4,576
Total investments	4,685
Short-term investments
Current
Investments including held for sale assets		170
Current investments	196
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	$ 196

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