Fair Value Measurements - Summary of Carrying Amounts and Corresponding Fair Values for Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities-held-to-maturity	$ 479,911	$ 575,850
Fixed maturity securities-available-for-sale	325,891	341,769
Equity securities	57,375	64,140
Short-term investments	36,927	57,431
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities-held-to-maturity	514,610	549,231
Fixed maturity securities-available-for-sale	325,891	341,769
Equity securities	57,375	64,140
Short-term investments	36,927	57,431
Cash and cash equivalents	90,952	70,722
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities-held-to-maturity	479,911	575,850
Fixed maturity securities-available-for-sale	325,891	341,769
Equity securities	57,375	64,140
Short-term investments	36,927	57,431
Cash and cash equivalents	$ 90,952	$ 70,722

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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