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Reinsurance (Tables)

12 Months Ended

Dec. 31, 2024

Reinsurance Disclosures [Abstract]

Effect Of Reinsurance And Retrocessional Reinsurance On Consolidated Premiums Written And Earned

The following tables summarize the effect of reinsurance and retrocessional reinsurance on premiums written and earned.

			Year Ended December 31, 2024
(dollars in thousands)			Direct						Assumed						Ceded						Net Premiums
Underwriting:
Written			$	8,860,015					$	1,691,858					$	(2,252,122)					$	8,299,751
Earned			$	8,801,477					$	1,628,408					$	(1,993,895)					$	8,435,990
Fronting:
Written			3,234,025						1,708,733						(4,946,334)						(3,576)
Earned			3,053,947						1,559,599						(4,617,124)						(3,578)
Consolidated:
Written			$	12,094,040					$	3,400,591					$	(7,198,456)					$	8,296,175
Earned			$	11,855,424					$	3,188,007					$	(6,611,019)					$	8,432,412

			Year Ended December 31, 2023
(dollars in thousands)			Direct						Assumed						Ceded						Net Premiums
Underwriting:
Written			$	8,657,266					$	1,620,366					$	(1,878,844)					$	8,398,788
Earned			$	8,363,710					$	1,616,630					$	(1,683,648)					$	8,296,692
Fronting:
Written			2,649,217						1,075,388						(3,725,818)						(1,213)
Earned			2,636,179						937,400						(3,574,792)						(1,213)
Consolidated:
Written			$	11,306,483					$	2,695,754					$	(5,604,662)					$	8,397,575
Earned			$	10,999,889					$	2,554,030					$	(5,258,440)					$	8,295,479

			Year Ended December 31, 2022
(dollars in thousands)			Direct						Assumed						Ceded						Net Premiums
Underwriting:
Written			$	8,085,812					$	1,761,726					$	(1,640,165)					$	8,207,373
Earned			$	7,379,766					$	1,589,920					$	(1,378,191)					$	7,591,495
Fronting:
Written			2,644,138						710,006						(3,358,127)						(3,983)
Earned			2,688,804						656,885						(3,349,392)						(3,703)
Consolidated:
Written			$	10,729,950					$	2,471,732					$	(4,998,292)					$	8,203,390
Earned			$	10,068,570					$	2,246,805					$	(4,727,583)					$	7,587,792

Effect of Reinsurance And Retrocessional Reinsurance on Incurred Losses and Loss Adjustment Expenses

The following table summarizes the effect of reinsurance and retrocessional reinsurance on losses and loss adjustment expenses in the Company's underwriting operations.

			Years ended December 31,
(dollars in thousands)			2024						2023						2022
Gross losses and loss adjustment expenses			$	6,970,871					$	6,817,630					$	5,281,424
Ceded losses and loss adjustment expenses			(1,917,318)						(1,496,265)						(834,648)
Net losses and loss adjustment expenses			$	5,053,553					$	5,321,365					$	4,446,776

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- Definition

Effects of Reinsurance on Losses [Table Text Block]

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- Definition

Tabular disclosure of the effects of reinsurance, for example, but not limited to, disclosure of direct, assumed, and ceded insurance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 605
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479032/944-605-50-1

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