Third-Party Reinsurance - Narrative (Details) - Third Point Re - P&C Insurance and Reinsurance (Ark/WM Outrigger) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Annual crediting rate	3.00%
Carrying value of investment	$ 20.3	$ 20.4

Carrying amount of assets as of the balance sheet date pertaining to amounts paid by 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_DepositContractsAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant