FEDERAL HOME LOAN BANK OF BOSTON ADVANCES - Federal Home Loan Bank of Boston ("FHLBB") advances (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Total
2015 advances		$ 791
2016 advances	$ 21	15,022
2017 advances		6,000
2018 advances	$ 7,000	$ 7,000
2019 advances
2020 advances	$ 14,337
2021 advances	5,621
Total advances	$ 26,979	$ 28,813
Callable (1)
2015 advances
2016 advances		$ 15,000
2017 advances		$ 6,000
2018 advances
2019 advances
2020 advances
2021 advances
Total advances		$ 21,000
Rate (2)
2015 rate		3.88%
2016 rate	5.06%	4.05%
2017 rate		3.99%
2018 rate	3.69%	3.69%
2019 rate
2020 rate	2.08%
2021 rate	2.39%
Total weighted average rate	2.58%	3.95%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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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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Describes the weighted average interest rate applicable to the specific 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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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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