Statutory Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statutory Accounting Practices [Line Items]
Dividends available to be paid	$ 7,400
Approximate increase in statutory capital and surplus resulting from discount of certain A&E liabilities	115	$ 120
Minimum statutory capital and surplus required to satisfy regulatory requirements	41,000	36,900
Statutory Accounting Practices, Permitted Practice, Amount	71	79
Other	147	85
PropertyAndCasualtySubsidiaries [Member]
Statutory Accounting Practices [Line Items]
Statutory capital and surplus	45,271	40,824
Statutory net income	8,699	4,028	$ 7,983
LifeSubsidiaries [Member] [Member]
Statutory Accounting Practices [Line Items]
Statutory capital and surplus	7,278	4,834
Statutory net income	$ 459	$ 1,425	$ 424

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-6

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-Section 50
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Amount of an item which resulted in a difference from applying state prescribed or permitted statutory accounting practices rather than statutory accounting practices prescribed by National Association of Insurance Commissioners.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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Amount of each item listed to reconcile the differences as of the balance sheet date resulting from applying state permitted statutory accounting practices rather than statutory accounting practices permitted by National Association of Insurance Commissioners.

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The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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-Name Accounting Standards Codification
-Section S99
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Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

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