Investments - Summary of Sales of Available-for-sale Fixed-Maturity Securities (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Schedule of Available-for-sale Securities [Line Items]
Proceeds			$ 11,494	$ 14,680
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds	$ 2,436	$ 14,644	11,494	14,680
Gross Realized Gains	11	576	13	$ 577
Gross Realized Losses	$ (3)	$ 0	$ (434)

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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Amount of cash inflow from sale 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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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