Investments (Schedule Of Investments In Partially-Owned Insurance Companies) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investment [Line Items]
Document Period End Date	Dec. 31, 2021
Carrying Value	$ 3,130	$ 2,813
Goodwill	15,213	15,400	$ 15,296
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	1,429	1,385
Huatai Group [Member] \| CHINA
Investment [Line Items]
Carrying Value	$ 2,698	$ 2,461
Ownership Percentage	47.00%	47.00%
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 1,355	$ 1,313
Huatai Life Insurance Co. [Member] \| CHINA
Investment [Line Items]
Carrying Value	$ 253	$ 201
Ownership Percentage	20.00%	20.00%
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 71	$ 69
Freisenbruch-Meyer \| Bermuda
Investment [Line Items]
Carrying Value	$ 10	$ 10
Ownership Percentage	40.00%	40.00%
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 3	$ 3
Chubb Arabia Cooperative Insurance Company [Member] \| Saudi Arabia
Investment [Line Items]
Carrying Value	$ 23	$ 23
Ownership Percentage	30.00%	30.00%
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 0	$ 0
Russian Reinsurance Company \| Russia
Investment [Line Items]
Carrying Value	$ 4	$ 4
Ownership Percentage	23.00%	23.00%
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 0	$ 0
ABR Reinsurance Capital Holdings Ltd. [Member] \| Bermuda
Investment [Line Items]
Carrying Value	$ 142	$ 114
Ownership Percentage	17.10%	16.00%
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 0	$ 0
Direct Ownership [Member] \| Huatai Group [Member] \| CHINA
Investment [Line Items]
Ownership Percentage	47.30%
Direct Ownership [Member] \| Huatai Life Insurance Co. [Member] \| CHINA
Investment [Line Items]
Ownership Percentage	20.00%
Indirect Ownership [Member] \| Huatai Life Insurance Co. [Member] \| CHINA
Investment [Line Items]
Ownership Percentage	37.70%
Total Direct and Indirect [Member] \| Huatai Life Insurance Co. [Member] \| CHINA
Investment [Line Items]
Ownership Percentage	57.70%

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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