Schedule IV Reinsurance (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Life insurance in-force
Gross Amount	$ 1,275,984	$ 1,147,723	$ 1,112,333
Ceded Amount	33,009	23,330	22,814
Assumed From Other Companies	23,605	22,511	21,230
Net Amount	$ 1,266,580	$ 1,146,904	$ 1,110,749
Percentage of Amount Assumed to Net	2.00%	2.00%	2.00%
Insurance revenues
Gross Amount	$ 21,959	$ 20,316	$ 18,867
Ceded Amount	1,716	1,568	1,381
Assumed From Other Companies	1,000	829	696
Premiums Earned, Net	$ 21,026	$ 19,390	$ 17,999
Percentage of Amount Assumed to Net	5.00%	4.00%	4.00%
Earned premiums and fees [Member]
Insurance revenues
Premiums Earned, Net	$ 21,243	$ 19,577	$ 18,182
Property and Casualty Insurance Products
Insurance revenues
Gross Amount	15,514	14,328	13,204
Ceded Amount	1,612	1,462	1,277
Assumed From Other Companies	826	654	568
Premiums Earned, Net	$ 14,728	$ 13,520	$ 12,495
Percentage of Amount Assumed to Net	6.00%	5.00%	5.00%
Life insurance and annuities
Insurance revenues
Gross Amount	$ 2,540	$ 2,341	$ 2,367
Ceded Amount	33	25	25
Assumed From Other Companies	76	77	46
Premiums Earned, Net	$ 2,583	$ 2,393	$ 2,388
Percentage of Amount Assumed to Net	3.00%	3.00%	2.00%
Accident and health insurance
Insurance revenues
Gross Amount	$ 3,905	$ 3,647	$ 3,296
Ceded Amount	71	81	79
Assumed From Other Companies	98	98	82
Premiums Earned, Net	$ 3,932	$ 3,664	$ 3,299
Percentage of Amount Assumed to Net	2.00%	3.00%	2.00%

Amount of life insurance issued and outstanding assumed from other entity, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column D
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
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-Publisher FASB
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount, before effect of reinsurance, of life insurance issued and outstanding, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Percentage of assumed life insurance contract issued and outstanding to life insurance contract issued and outstanding after effect of reinsurance, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

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