Value of Business Acquired, Goodwill, and Other Intangible Assets (Roll-forward of Goodwill by Business Segment) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($)
Goodwill [Roll Forward]
Balance at beginning of period	$ 15,213
Foreign exchange revaluation and other	(446)
Balance at end of period	16,107
North America Commercial P&C Insurance [Member]
Goodwill [Roll Forward]
Balance at beginning of period	6,972
Foreign exchange revaluation and other	(11)
Balance at end of period	6,961
North America Personal P&C Insurance [Member]
Goodwill [Roll Forward]
Balance at beginning of period	2,240
Foreign exchange revaluation and other	(4)
Balance at end of period	2,236
North America Agricultural Insurance [Member]
Goodwill [Roll Forward]
Balance at beginning of period	134
Foreign exchange revaluation and other	0
Balance at end of period	134
Overseas General Insurance [Member]
Goodwill [Roll Forward]
Balance at beginning of period	4,653
Foreign exchange revaluation and other	(431)
Balance at end of period	4,325
Global Reinsurance [Member]
Goodwill [Roll Forward]
Balance at beginning of period	371
Foreign exchange revaluation and other	0
Balance at end of period	371
Segment Life [Member]
Goodwill [Roll Forward]
Balance at beginning of period	843
Foreign exchange revaluation and other	0
Balance at end of period	2,080
Cigna's Life Insurance Business in Asia-Pacific Markets [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	1,340
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] | North America Commercial P&C Insurance [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	0
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] | North America Personal P&C Insurance [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	0
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] | North America Agricultural Insurance [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	0
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] | Overseas General Insurance [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	103
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] | Global Reinsurance [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	0
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] | Segment Life [Member]
Goodwill [Roll Forward]
Acquisition of Cigna's business in Asia	$ 1,237