Investments - Investments by Category (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Current
Investments including held for sale assets		$ 1,264
Investments classified as assets of business held for sale		(344)
Investments per Consolidated Balance Sheets	$ 905	920
Long-term
Investments including held for sale assets		23,203
Investments classified as assets of business held for sale		(4,765)
Investments per Consolidated Balance Sheets	16,288	18,438
Total
Investments including held for sale assets		24,467
Investments classified as assets of business held for sale		(5,109)
Investments per Consolidated Balance Sheets	17,193	19,358
Debt securities
Current
Investments including held for sale assets		796
Investments per Consolidated Balance Sheets	654
Long-term
Investments including held for sale assets		16,162
Investments per Consolidated Balance Sheets	9,218
Total
Investments including held for sale assets		16,958
Investments per Consolidated Balance Sheets	9,872
Equity securities
Current
Investments including held for sale assets		0
Investments per Consolidated Balance Sheets	45
Long-term
Investments including held for sale assets		603
Investments per Consolidated Balance Sheets	577
Total
Investments including held for sale assets		603
Investments per Consolidated Balance Sheets	622
Commercial mortgage loans
Current
Investments including held for sale assets		40
Investments per Consolidated Balance Sheets	67
Long-term
Investments including held for sale assets		1,526
Investments per Consolidated Balance Sheets	1,547
Total
Investments including held for sale assets		1,566
Investments per Consolidated Balance Sheets	1,614
Policy loans
Current
Investments including held for sale assets		0
Investments per Consolidated Balance Sheets	0
Long-term
Investments including held for sale assets		1,338
Investments per Consolidated Balance Sheets	1,218
Total
Investments including held for sale assets		1,338
Investments per Consolidated Balance Sheets	1,218
Other long-term investments
Current
Investments including held for sale assets		0
Investments per Consolidated Balance Sheets	0
Long-term
Investments including held for sale assets		3,574
Investments per Consolidated Balance Sheets	3,728
Total
Investments including held for sale assets		3,574
Investments per Consolidated Balance Sheets	3,728
Short-term investments
Current
Investments including held for sale assets		428
Investments per Consolidated Balance Sheets	139
Long-term
Investments including held for sale assets		0
Investments per Consolidated Balance Sheets	0
Total
Investments including held for sale assets		$ 428
Investments per Consolidated Balance Sheets	$ 139

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