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Loans and Allowance for Credit Losses on Loans - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2025	Dec. 31, 2024
Accrued interest receivable	$ 1,400,000	$ 1,300,000
Loans outstanding	3,900,000	4,300,000
Loans past due over 90 days still accruing interest	0	0
Maximum [Member]
Reduced credit administration process for commercial relationships	500,000
Residential Real Estate [Member]
Loans collateralized by real estate	$ 0	$ 0

X

- Definition

Loans collaterized by real estate properties..

+ References

No definition available.

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- Definition

Reduced credit administration process for commercial relationships.

+ References

No definition available.

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- Definition

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-Publisher FASB
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- Definition

Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

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