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Nephila Related Party Disclosures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Gross written premiums	$ 14,002,237	$ 13,201,682	$ 11,438,682
Ceded written premium	5,604,662	4,998,292	4,318,951
Program services and other fronting [Member] | Nephila Reinsurers [Member]
Related Party Transaction [Line Items]
Gross written premiums	1,064,121	1,008,851	689,153
Ceded written premium	1,064,121	1,008,851	689,153
Underwriting Operations [Member]
Related Party Transaction [Line Items]
Gross written premiums	10,277,632	9,847,538	8,485,929
Underwriting Operations [Member] | Nephila Reinsurers [Member]
Related Party Transaction [Line Items]
Ceded written premium	$ 52,295	$ 65,648	$ 54,970

X

- Definition

Amount of written premiums ceded to other entities.

+ References

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-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
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