Investments - Schedule of Net Realized (Losses) Gains on Debt Securities Available-for-sale (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Securities Available-for-Sale
Total realized gains	$ 0	$ 28	$ 0	$ 32
Total realized losses	(9)	(130)	(11)	(150)
Net realized (losses) gains	(9)	(102)	(11)	(118)
Debt Securities Available-for-sale, Fair Value at Sale
Total realized gains, Fair Value at Sale	0	1,291	0	2,336
Total realized losses, Fair Value at Sale	308	4,546	598	6,096
Net realized gains (losses), Fair Value at Sale	$ 308	$ 5,837	$ 598	$ 8,432

Available for sale securities gross realized gain loss fair value.

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Debt securities available for sale realized gain fair value.

+ References

No definition available.

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- Definition

Debt securities available for sale realized gain loss fair value.

+ References

No definition available.

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- Definition

Debt securities available for sale realized loss fair value.

+ References

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- References

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

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- Definition

Amount of realized gain (loss) on 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/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

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- Definition

Amount of realized 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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