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Investments (Schedule Of Investments In Partially-Owned Insurance Companies) (Details) - USD ($) $ in Millions		3 Months Ended
	Jan. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Investment [Line Items]
Carrying Value			$ 2,877	$ 3,130
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			1,315	1,429
Goodwill			$ 16,287	$ 15,213	$ 15,400
Huatai Group [Member] \| Subsequent Event [Member]
Investment [Line Items]
Equity method investment, additional 22.0 percent agreed on	22.00%
CHINA \| Huatai Group [Member]
Investment [Line Items]
Ownership Percentage			47.00%	47.00%
CHINA \| Huatai Group [Member] \| Subsequent Event [Member]
Investment [Line Items]
equity method investment, additional 16.9 percentage obtained		16.90%
CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage			20.00%	20.00%
Bermuda \| Freisenbruch-Meyer
Investment [Line Items]
Ownership Percentage			40.00%	40.00%
Bermuda \| ABR Reinsurance Capital Holdings Ltd. [Member]
Investment [Line Items]
Ownership Percentage			19.00%	17.00%
Saudi Arabia \| Chubb Arabia Cooperative Insurance Company [Member]
Investment [Line Items]
Ownership Percentage			30.00%	30.00%
Russia \| Russian Reinsurance Company
Investment [Line Items]
Ownership Percentage			23.00%	23.00%
Huatai Group [Member] \| CHINA
Investment [Line Items]
Carrying Value			$ 2,490	$ 2,698
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			1,247	1,355
Huatai Life Insurance Co. [Member] \| CHINA
Investment [Line Items]
Carrying Value			215	253
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			65	71
Freisenbruch-Meyer \| Bermuda
Investment [Line Items]
Carrying Value			11	10
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			24	23
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			0	0
Russian Reinsurance Company \| Russia
Investment [Line Items]
Carrying Value			0	4
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			0	0
ABR Reinsurance Capital Holdings Ltd. [Member] \| Bermuda
Investment [Line Items]
Carrying Value			137	142
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity			$ 0	$ 0
ABR Reinsurance Capital Holdings Ltd. [Member] \| Bermuda \| ABR Reinsurance Capital Holdings Ltd. [Member]
Investment [Line Items]
Ownership Percentage			18.80%
Total Direct and Indirect [Member] \| CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage			57.70%
Direct Ownership [Member] \| Huatai Group [Member]
Investment [Line Items]
Ownership Percentage			47.30%
Direct Ownership [Member] \| Huatai Group [Member] \| Subsequent Event [Member]
Investment [Line Items]
Ownership Percentage	64.20%
Direct Ownership [Member] \| CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage			20.00%
Indirect Ownership [Member] \| CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage			37.70%