Fair Value Measurements - Summary of Carrying Amounts and Corresponding Fair Values for Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities, fair value	$ 461,681	$ 473,092
Fixed maturity securities-available-for-sale	290,673	317,064
Equity securities	61,923	57,147
Short-term investments	38,641	0
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities, fair value	475,322	483,575
Fixed maturity securities-available-for-sale	290,673	317,064
Equity securities	61,923	57,147
Short-term investments	38,641	0
Cash and cash equivalents	33,375	38,682
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities, fair value	461,681	473,092
Fixed maturity securities-available-for-sale	290,673	317,064
Equity securities	61,923	57,147
Short-term investments	38,641	0
Cash and cash equivalents	$ 33,375	$ 38,682

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

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of investment in marketable security.

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