Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	$ 342,972	$ 341,769
Equity securities, Fair Value	69,156	64,140
Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	342,972	341,769
Total	412,128	405,909
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	20,075	20,948
Total	89,231	85,088
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	322,897	320,821
Total	322,897	320,821
Fair Value, Measurements, Recurring [Member] \| States and Political Subdivisions [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	202,236	216,306
Fair Value, Measurements, Recurring [Member] \| States and Political Subdivisions [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	202,236	216,306
Fair Value, Measurements, Recurring [Member] \| Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	113,699	96,426
Fair Value, Measurements, Recurring [Member] \| Corporate Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	113,699	96,426
Fair Value, Measurements, Recurring [Member] \| U.S. Agency-Based Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	6,962	8,089
Fair Value, Measurements, Recurring [Member] \| U.S. Agency-Based Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	6,962	8,089
Fair Value, Measurements, Recurring [Member] \| U.S. Treasury Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	20,075	20,948
Fair Value, Measurements, Recurring [Member] \| U.S. Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale fixed maturity, Fair Value	20,075	20,948
Fair Value, Measurements, Recurring [Member] \| Common Stock [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities, Fair Value	69,156	64,140
Fair Value, Measurements, Recurring [Member] \| Common Stock [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities, Fair Value	$ 69,156	$ 64,140

Available for sale securities debt securities and equity securities Fv-Ni.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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