Reinsurance (Reinsurance Deposit Part B - Narrative) (Details) - USD ($) $ in Billions	Dec. 31, 2023	Dec. 31, 2022
Reinsurance Disclosures [Abstract]
Deposit Contracts, Assets	$ 7.4	$ 5.8
Deposit Contracts, Liabilities	$ 4.0	$ 4.0

Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer or reinsurer from the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483081/340-30-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483054/340-30-50-1

Name:	us-gaap_DepositContractsLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant