Investments - Investments by Category (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Current
Investments including assets of business held for sale		$ 1,264
Investments classified as assets of business held for sale		(344)
Investments per Consolidated Balance Sheets	$ 783	920
Long-term
Investments including assets of business held for sale		23,203
Investments classified as assets of business held for sale		(4,765)
Investments per Consolidated Balance Sheets	16,273	18,438
Total
Investments including assets of business held for sale		24,467
Investments classified as assets of business held for sale		(5,109)
Investments per Consolidated Balance Sheets	17,056	19,358
Debt securities
Current
Investments including assets of business held for sale		796
Investments per Consolidated Balance Sheets	567
Long-term
Investments including assets of business held for sale		16,162
Investments per Consolidated Balance Sheets	9,263
Total
Investments including assets of business held for sale		16,958
Investments per Consolidated Balance Sheets	9,830
Equity securities
Current
Investments including assets of business held for sale		0
Investments per Consolidated Balance Sheets	67
Long-term
Investments including assets of business held for sale		603
Investments per Consolidated Balance Sheets	604
Total
Investments including assets of business held for sale		603
Investments per Consolidated Balance Sheets	671
Commercial mortgage loans
Current
Investments including assets of business held for sale		40
Investments per Consolidated Balance Sheets	13
Long-term
Investments including assets of business held for sale		1,526
Investments per Consolidated Balance Sheets	1,557
Total
Investments including assets of business held for sale		1,566
Investments per Consolidated Balance Sheets	1,570
Policy loans
Current
Investments including assets of business held for sale		0
Investments per Consolidated Balance Sheets	0
Long-term
Investments including assets of business held for sale		1,338
Investments per Consolidated Balance Sheets	1,210
Total
Investments including assets of business held for sale		1,338
Investments per Consolidated Balance Sheets	1,210
Other long-term investments
Current
Investments including assets of business held for sale		0
Investments per Consolidated Balance Sheets	0
Long-term
Investments including assets of business held for sale		3,574
Investments per Consolidated Balance Sheets	3,639
Total
Investments including assets of business held for sale		3,574
Investments per Consolidated Balance Sheets	3,639
Short-term investments
Current
Investments including assets of business held for sale		428
Investments per Consolidated Balance Sheets	136
Long-term
Investments including assets of business held for sale		0
Investments per Consolidated Balance Sheets	0
Total
Investments including assets of business held for sale		$ 428
Investments per Consolidated Balance Sheets	$ 136

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