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Statutory Financial Information - Additional Information (Detail) - USD ($) $ in Thousands													12 Months Ended
	Dec. 31, 2024	Oct. 07, 2024	Jun. 28, 2024	Mar. 28, 2024	Dec. 29, 2023	Oct. 16, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 30, 2022	Oct. 11, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statutory Accounting Practices [Line Items]
Dividends	$ 4,790	$ 4,782	$ 4,774	$ 4,752	$ 3,385	$ 3,385	$ 3,375	$ 3,410	$ 3,389	$ 3,616	$ 3,602	$ 3,597	$ 19,116	$ 13,469	$ 14,543
Penn Patriot Insurance Company
Statutory Accounting Practices [Line Items]
Dividends													40,000
Diamond State Insurance Company
Statutory Accounting Practices [Line Items]
Maximum amount of dividends that could be paid in 2024 under applicable laws and regulations without regulatory approval	11,000												11,000
Penn-Star Insurance Company
Statutory Accounting Practices [Line Items]
Maximum amount of dividends that could be paid in 2024 under applicable laws and regulations without regulatory approval	$ 13,800												$ 13,800

X

- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477787/942-405-45-2

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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- Definition

Amount of dividends that can be declared or paid without approval of regulatory agency.

+ References

No definition available.

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