Number of internal loan rating grades.

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- Definition

Schedule of loans, allowance for loan losses and credit quality.

+ References

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- Definition

Threshold limit for loans receivable.

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No definition available.

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- Definition

Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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- Definition

Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Loans, Allowance for Credit Losses and Credit Quality - Additional Information (Details)	3 Months Ended				9 Months Ended
	Sep. 30, 2024 USD ($)	Jun. 30, 2024 Grade	Mar. 31, 2024 Grade	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Schedule Of Loans Allowance For Loan Losses And Credit Quality [Line Items]
Carrying value of loans pledged	$ 1,114,943,000				$ 1,114,943,000		$ 1,039,789,000
Interest income recognized on nonaccrual loans	13,000			$ 12,000	49,000	$ 26,000
Number of Internal Loan Rating Grades \| Grade		10	7
Loan restructurings	0			$ 0	0	$ 0
FHLBB \| Loans Pledged
Schedule Of Loans Allowance For Loan Losses And Credit Quality [Line Items]
Carrying value of loans pledged	676,500,000				676,500,000		553,000,000
Commercial And Industrial Loans
Schedule Of Loans Allowance For Loan Losses And Credit Quality [Line Items]
Threshold limit for loans receivable	500,000				500,000
Commercial Real Estate Loans
Schedule Of Loans Allowance For Loan Losses And Credit Quality [Line Items]
Threshold limit for loans receivable	2,000,000				2,000,000
Residential Real Estate
Schedule Of Loans Allowance For Loan Losses And Credit Quality [Line Items]
Mortgage loans in process of foreclosure	$ 0				$ 0		$ 0