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Acquisitions (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
Acquisitions (Details) - USD ($) $ in Millions	Jul. 01, 2022	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2022
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Jul. 01, 2022
Payments to Acquire Businesses, Gross	$ 5,360
Huatai Group [Member]
Business Acquisition [Line Items]
Equity method investment, additional 31.8 percent agreed on			31.80%
Purchase of incremental ownership interest			$ 2,200
Deposits Assets			$ 1,100
Payment to acquire additional ownership interest in equity method investment		$ 113		$ 500
Equity method investment, additional 7.1 percentage agreed on				7.10%
Huatai Group [Member] \| Direct ownership
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage					47.30%