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Investment Securities - Narrative (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Increase (decrease) in gross unrealized losses	$ (176,900,000)
Investment securities available-for-sale, at fair value	0	$ 867,000
Securities held-to-maturity	0	0
Corporate debt
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Investment securities available-for-sale, at fair value	$ 0	$ 867,000

X

- Definition

Amount excluding accrued interest, of allowance for credit 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/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

+ Details

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X

- Definition

Amount excluding accrued interest, of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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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/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Debt Securities, Available-for-Sale, Increase (Decrease) in Unrealized Losses

+ References

No definition available.

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