FHLBB and Correspondent Bank Overnight Borrowings

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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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Weighted average interest rate of debt outstanding.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Principal amount of long-term debt and capital lease obligation 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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No definition available.

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Principal amount of long-term debt and capital lease obligation 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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Principal amount of long-term debt and capital lease obligation 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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Principal amount of long-term debt and capital lease obligation 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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No definition available.

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Principal amount of long-term debt and capital lease obligation 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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Principal amount of long-term debt and capital lease obligation 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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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next 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, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Borrowings (Summary of Short term and Long term Borrowings and Subordinated Debentures) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Securities Sold under Agreements to Repurchase	$ 211,608	$ 162,439
Total short-term borrowings	$ 211,608	$ 162,439
FHLBB Borrowings [Member]
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	0.00%	0.98%
Long-term Debt and Capital Lease Obligations, Repayments of Principal in Next Twelve Months	$ 0
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2022	0
2023	0
2025	0
Customer repurchase agreements
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2021	211,608
FHLBB and correspondent bank overnight borrowings
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2021	$ 0
Long-term Debt
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	0.00%	0.98%
Long-term Debt and Capital Lease Obligations, Repayments of Principal in Next Twelve Months	$ 0
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2022	0
2023	0
2024
2025	0
Thereafter	0
Total long-term borrowings	$ 0	$ 25,000
Subordinated Debt and Junior Subordinated Debt
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	5.50%	5.50%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2025	$ 0
Thereafter	44,331
Total long-term borrowings	$ 44,331	$ 59,331
Subordinated Debt \| Subordinated debentures
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	0.00%	5.50%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2025	$ 0
Thereafter	0
Total long-term borrowings	0	$ 15,000
Debt Issuance Costs, Net	0	251	$ 115
Short-term Debt
Debt Instrument [Line Items]
Total short-term borrowings	$ 211,608	$ 162,439
Weighted Average Rate (as a percent)	0.25%	0.34%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2021	$ 211,608
Short-term Debt \| Customer repurchase agreements
Debt Instrument [Line Items]
Securities Sold under Agreements to Repurchase	$ 211,608	$ 162,439
Weighted Average Rate (as a percent)	0.25%	0.34%
Short-term Debt \| FHLBB and correspondent bank overnight borrowings
Debt Instrument [Line Items]
FHLBB and correspondent bank overnight borrowings	$ 0	$ 0
Weighted Average Rate (as a percent)	0.00%	0.00%
Long-term Debt \| FHLBB Borrowings [Member]
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Federal Home Loan Bank Advances	$ 0	$ 25,000
Subsidiary One [Member] \| Junior Subordinated Debt
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	5.50%	5.50%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
Thereafter	$ 36,083
Total long-term borrowings	$ 36,083	$ 36,083
Subsidiary Two [Member] \| Junior Subordinated Debt
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	5.48%	5.48%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
Thereafter	$ 8,248
Total long-term borrowings	$ 8,248	$ 8,248