Federal Home Loan Bank of Boston advances (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
F H L B B Advances Total [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advance, Maturity, Year Three		$ 7,656
Federal Home Loan Bank, Advance, Maturity, Year Four	10,000
Long-Term Federal Home Loan Bank Advances	$ 10,000	$ 7,656
F H L B B Advances Rate [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advance, Maturity, Average Interest Rate, Year Three		1.39%
Federal Home Loan Bank, Advance, Maturity, Average Interest Rate, Year Four	4.43%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	4.43%	1.39%

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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