Investments maturity period using default rate.

No definition available.

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- Definition

Number of fixed maturity securities, held to maturity allowance for credit loss.

+ References

No definition available.

+ Details

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- Definition

Number of individual fixed maturity securities in unrealized loss position.

+ References

No definition available.

+ Details

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- Definition

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

+ References

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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- 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

No definition available.

+ Details

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- Definition

Amount of realized gain (loss) on investment.

+ References

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Investments - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026 USD ($) Security	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) Security	Sep. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)
Marketable Securities [Line Items]
Individual fixed maturity held in unrealized loss position \| Security	221		221
Number of fixed maturity securities, allowance for credit loss \| Security	253		253
Fixed maturity securities, held-to-maturity, allowance for credit losses	$ 58		$ 58		$ 60	$ 73
Fixed maturity securities, available-for-sale, allowance for credit losses	0		0			0
Net realized gains (losses) on investments	(54)	$ 0	(144)	$ 3,118
Net unrealized gains (losses) on equity securities	(193)	$ 4,117	6,267	$ 2,794
Corporate Bonds [Member]
Marketable Securities [Line Items]
Fixed maturity securities, held-to-maturity, allowance for credit losses	$ 38		$ 38		39	50
States and Political Subdivisions [Member]
Marketable Securities [Line Items]
Number of fixed maturity securities, allowance for credit loss \| Security	244		244
Fixed maturity securities, held-to-maturity, allowance for credit losses	$ 20		$ 20		$ 21	$ 23
Corporate Fixed Income Securities [Member] \| Maximum [Member]
Marketable Securities [Line Items]
Investments maturity period using default rate			20 years