Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Purchases of investments			$ 8,300,000	$ 34,300,000
Proceeds from the sales and maturities of securities available-for-sale			6,900,000	32,200,000
Transfers between Level 1, Level 2 and Level 3 securities	$ 0	$ 0	0	0
Cash collateral deposit	1,700,000		1,700,000
Credit losses on available-for-sale securities	$ 0	$ 0	$ 0	$ 0

Available for sale securities on credit losses

No definition available.

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- Definition

Cash collateral for derivative deposit.

+ References

No definition available.

+ Details

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers between Level 1, Level 2 and Level 3 securities.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

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- Definition

The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-13

+ Details

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- Definition

The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

+ References

No definition available.

+ Details

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