Borrowings (Summary of Short term and Long term Borrowings and Subordinated Debentures) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Securities Sold under Agreements to Repurchase	$ 196,451	$ 211,608
Total short-term borrowings	265,176	$ 211,608
Customer repurchase agreements
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2023	196,451
2024	0
2025	0
2026	0
2027	0
Thereafter	0
FHLBB and correspondent bank overnight borrowings
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2023	68,725
2024	0
2025	0
2026	0
2027	0
Thereafter	$ 0
Subordinated Debt and Junior Subordinated Debt
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	4.76%	5.50%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2023	$ 0
2024	0
2025	0
2026	0
2027	0
Thereafter	44,331
Total long-term borrowings	44,331	$ 44,331
Short-term Debt
Debt Instrument [Line Items]
Total short-term borrowings	$ 265,176	$ 211,608
Weighted Average Rate (as a percent)	1.98%	0.25%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2023	$ 265,176
2024	0
2025	0
2026	0
2027	0
Thereafter	0
Short-term Debt \| Customer repurchase agreements
Debt Instrument [Line Items]
Securities Sold under Agreements to Repurchase	$ 196,451	$ 211,608
Weighted Average Rate (as a percent)	1.00%	0.25%
Short-term Debt \| FHLBB and correspondent bank overnight borrowings
Debt Instrument [Line Items]
FHLBB and correspondent bank overnight borrowings	$ 68,725	$ 0
Weighted Average Rate (as a percent)	4.78%	0.00%
Subsidiary One [Member] \| Junior Subordinated Debt
Debt Instrument [Line Items]
Weighted Average Rate (as a percent)	4.62%	5.50%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2023	$ 0
2024	0
2025	0
2026	0
2027	0
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)	5.39%	5.48%
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2023	$ 0
2024	0
2025	0
2026	0
2027	0
Thereafter	8,248
Total long-term borrowings	$ 8,248	$ 8,248

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