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Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Assets And Liabilities Measured At Fair value, On A Recurring Basis

The following tables present the assets and liabilities measured at fair value as of December 31, 2024 and 2023 by level:

(In thousands)			Total						Level 1						Level 2						Level 3
December 31, 2024
Assets:
Fixed maturity securities available for sale:
U.S. government and government agency			$	2,235,341					$	—					$	2,235,341					$	—
State and municipal			2,294,644						—						2,294,644						—
Mortgage-backed securities			3,765,490						—						3,765,490						—
Asset-backed securities			3,885,012						—						3,885,012						—
Corporate			8,417,641						—						8,397,974						19,667
Foreign government			1,755,325						—						1,755,325						—
Total fixed maturity securities available for sale			22,353,453						—						22,333,786						19,667
Equity securities:
Common stocks			760,167						757,115						1,011						2,041
Preferred stocks			443,621						—						439,947						3,674
Total equity securities			1,203,788						757,115						440,958						5,715
Arbitrage trading account			1,122,599						1,062,459						56,630						3,510
Total			$	24,679,840					$	1,819,574					$	22,831,374					$	28,892
Liabilities:
Trading account securities sold but not yet purchased			$	73,358					$	73,358					$	—					$	—
December 31, 2023
Assets:
Fixed maturity securities available for sale:
U.S. government and government agency			$	1,716,731					$	—					$	1,716,731					$	—
State and municipal			2,634,422						—						2,634,422						—
Mortgage-backed securities			2,266,455						—						2,266,455						—
Asset-backed securities			4,187,040						—						4,187,040						—
Corporate			7,654,059						—						7,654,059						—
Foreign government			1,666,229						—						1,666,229						—
Total fixed maturity securities available for sale			20,124,936						—						20,124,936						—
Equity securities:
Common stocks			838,054						835,338						1,158						1,558
Preferred stocks			252,293						—						248,598						3,695
Total equity securities			1,090,347						835,338						249,756						5,253
Arbitrage trading account			938,049						546,110						388,167						3,772
Total			$	22,153,332					$	1,381,448					$	20,762,859					$	9,025
Liabilities:
Trading account securities sold but not yet purchased			$	9,357					$	9,357					$	—					$	—

Summarize Changes In Level 3 Assets and Liabilities

The following tables summarize changes in Level 3 assets and liabilities for the years ended December 31, 2024 and 2023:

			Gains (Losses) Included in:
(In thousands)			Beginning Balance						Earnings (Losses)						Other Comprehensive Losses						Impairments						Purchases						Sales						Paydowns/Maturities						Transfers In / Out															Ending Balance
Year ended December 31, 2024
Assets:
Fixed maturity securities available for sale:
Corporate			$	—					$	—					$	(333)					$	—					$	—					$	—					$	—					$	20,000														$	19,667
Total			—						—						(333)						—						—						—						—						20,000															19,667
Equity securities:
Common stocks			1,558						611						—						—						—						(128)						—						—															2,041
Preferred stocks			3,695						36						—						—						—						(57)						—						—															3,674
Total			5,253						647						—						—						—						(185)						—						—															5,715
Arbitrage trading account			3,772						(261)						—						—						—						(38)						—						37															3,510
Total			$	9,025					$	386					$	(333)					$	—					$	—					$	(223)					$	—					$	20,037														$	28,892
Year ended December 31, 2023
Assets:
Fixed maturity securities available for sale:
Corporate			$	—					$	—					$	—					$	—					$	—					$	—					$	—					$	—														$	—
Total			—						—						—						—						—						—						—						—															—
Equity securities:
Common stocks			2,599						(1,041)						—						—						—						—						—						—															1,558
Preferred stocks			11,299						(3)						—						(7,601)						—												—						—															3,695
Total			13,898						(1,044)						—						(7,601)						—						—						—						—															5,253
Arbitrage trading account			3,590						117						—						—						—						—						—						65															3,772
Total			$	17,488					$	(927)					$	—					$	(7,601)					$	—					$	—					$	—					$	65														$	9,025

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- References

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- Definition

Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

+ References

No definition available.

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