Basis of Presentation (Details)	12 Months Ended
Dec. 31, 2025 USD ($) segment office	Dec. 31, 2024 USD ($)
Basis of Presentation
Number of full-service banking offices \| office	147
Number of lending offices \| office	3
Impairment of restricted securities	$ 0	$ 0
Number of days loans past due placed on non accrual status	90 days
Allowance for credit loss, completion of revision, period from forecast start date	5 years
Adjustment of allowance for credit loss related to merger	$ 24,800,000
BOLI, as percentage of capital plus reserves, maximum, individual carrier (as a percent)	10.00%
BOLI, as percentage of capital plus reserves, maximum, aggregate (as a percent)	25.00%
Number of operating segments \| segment	1
Number of reportable segments \| segment	1
Legacy Berkshire Portfolio
Basis of Presentation
Adjustment of allowance for credit loss related to merger	$ 5,600,000
Minimum
Basis of Presentation
Allowance for credit loss, start of revision, period from forecast start date	2 years
Lease term	1 year
Maximum
Basis of Presentation
Allowance for credit loss, start of revision, period from forecast start date	3 years
Lease term	18 years

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Allowance For Credit Loss, Start of Revision, Period From Forecast Start Date

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Represents the maximum bank owned life insurance as a percentage of aggregate of capital and reserves.

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Bank Owned Life Insurance Maximum As Percentage Of Capital Plus Reserves, Individual Carrier

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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.

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Financing Receivable, Qualitative Adjustments To Models For Credit Risk, Net

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Impairment Of Restricted Investments

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Represents the number of full service banking offices operated by the entity.

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Represents the number of days past due that loans are placed on non-accrual status.

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Number Of Lending Offices

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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