Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479584/944-310-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479838/944-20-50-5

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479616/944-310-45-6

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (cc)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-3

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
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-URI https://asc.fasb.org//1943274/2147480081/944-40-50-3

Name:	us-gaap_ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Reinsurance and Indemnification - Reinsurance and indemnification recoverables, net (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Reinsurance
Reinsurance and indemnification recoverables, net	$ 9,151	$ 9,619
Property and casualty
Reinsurance
Paid and due from reinsurers and indemnitors	259	291
Unpaid losses estimated (including IBNR)	8,730	9,176	$ 8,950	$ 9,479
Reinsurance and indemnification recoverables, net	8,989	9,467
Accident and health insurance
Reinsurance
Reinsurance and indemnification recoverables, net	$ 162	$ 152