Regulations and Supervision - Actual Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Banking Regulation, Total Capital [Abstract]
Total Capital (to risk-weighted assets), Actual Amount	$ 780,472	$ 735,187
Total Capital (to risk-weighted assets), Actual Ratio	0.144	0.142
Total Capital (to risk-weighted assets), Minimum Capital Required, Amount	$ 568,431	$ 524,345
Total Capital (to risk-weighted assets), Minimum Capital Required, Ratio	0.105	0.105
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Amount	$ 541,363	$ 516,519
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio	0.100	0.100
Common Equity Tier 1 Capital (To Risk-weighted Assets)
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Amount	$ 730,330	$ 688,425
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Ratio	0.135	0.133
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount	$ 378,954	$ 361,563
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio	7.00%	7.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount	$ 351,886	$ 335,737
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio	6.50%	6.50%
Tier 1 Capital (To Risk-weighted Assets)
Tier 1 Capital (to risk-weighted assets), Actual Amount	$ 730,330	$ 688,425
Tier 1 Capital (to risk-weighted assets), Actual Ratio	0.135	0.133
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount	$ 460,159	$ 439,041
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio	0.085	0.085
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount	$ 433,091	$ 413,215
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio	0.080	0.080
Tier 1 Leverage Capital (To Average Assets)
Tier 1 Capital (to average assets), Actual Amount	$ 730,330	$ 688,425
Tier 1 Capital (to average assets), Actual Ratio	0.093	0.087
Tier 1 Capital (to average assets), Minimum Capital Required, Amount	$ 312,695	$ 315,820
Tier 1 Capital (to average assets), Minimum Capital Required, Ratio	0.040	0.040
Tier 1 Capital (to average assets), Required to be Well Capitalized, Amount	$ 390,868	$ 394,775
Tier 1 Capital (to average assets), Required to be Well Capitalized, Ratio	0.050	0.050
Castile
Banking Regulation, Total Capital [Abstract]
Total Capital (to risk-weighted assets), Actual Amount		$ 160,757
Total Capital (to risk-weighted assets), Actual Ratio		0.122
Total Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 138,104
Total Capital (to risk-weighted assets), Minimum Capital Required, Ratio		0.105
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 131,527
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		0.100
Common Equity Tier 1 Capital (To Risk-weighted Assets)
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Amount		$ 149,154
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Ratio		0.113
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 92,069
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio		7.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 85,493
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		6.50%
Tier 1 Capital (To Risk-weighted Assets)
Tier 1 Capital (to risk-weighted assets), Actual Amount		$ 149,154
Tier 1 Capital (to risk-weighted assets), Actual Ratio		0.113
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 111,798
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio		0.085
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 105,222
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		0.080
Tier 1 Leverage Capital (To Average Assets)
Tier 1 Capital (to average assets), Actual Amount		$ 149,154
Tier 1 Capital (to average assets), Actual Ratio		0.079
Tier 1 Capital (to average assets), Minimum Capital Required, Amount		$ 75,935
Tier 1 Capital (to average assets), Minimum Capital Required, Ratio		0.040
Tier 1 Capital (to average assets), Required to be Well Capitalized, Amount		$ 94,918
Tier 1 Capital (to average assets), Required to be Well Capitalized, Ratio		0.050
Mahopac
Banking Regulation, Total Capital [Abstract]
Total Capital (to risk-weighted assets), Actual Amount		$ 136,247
Total Capital (to risk-weighted assets), Actual Ratio		0.127
Total Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 112,649
Total Capital (to risk-weighted assets), Minimum Capital Required, Ratio		0.105
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 107,285
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		0.100
Common Equity Tier 1 Capital (To Risk-weighted Assets)
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Amount		$ 126,718
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Ratio		0.118
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 75,100
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio		7.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 69,735
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		6.50%
Tier 1 Capital (To Risk-weighted Assets)
Tier 1 Capital (to risk-weighted assets), Actual Amount		$ 126,718
Tier 1 Capital (to risk-weighted assets), Actual Ratio		0.118
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 91,192
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio		0.085
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 85,282
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		0.080
Tier 1 Leverage Capital (To Average Assets)
Tier 1 Capital (to average assets), Actual Amount		$ 126,718
Tier 1 Capital (to average assets), Actual Ratio		0.081
Tier 1 Capital (to average assets), Minimum Capital Required, Amount		$ 62,815
Tier 1 Capital (to average assets), Minimum Capital Required, Ratio		0.040
Tier 1 Capital (to average assets), Required to be Well Capitalized, Amount		$ 78,519
Tier 1 Capital (to average assets), Required to be Well Capitalized, Ratio		0.050
VIST
Banking Regulation, Total Capital [Abstract]
Total Capital (to risk-weighted assets), Actual Amount		$ 173,889
Total Capital (to risk-weighted assets), Actual Ratio		0.136
Total Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 134,403
Total Capital (to risk-weighted assets), Minimum Capital Required, Ratio		0.105
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 128,003
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		0.100
Common Equity Tier 1 Capital (To Risk-weighted Assets)
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Amount		$ 163,145
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Ratio		0.128
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 89,602
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio		7.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 83,202
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		6.50%
Tier 1 Capital (To Risk-weighted Assets)
Tier 1 Capital (to risk-weighted assets), Actual Amount		$ 163,145
Tier 1 Capital (to risk-weighted assets), Actual Ratio		0.128
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount		$ 108,803
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio		0.085
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount		$ 102,403
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio		0.080
Tier 1 Leverage Capital (To Average Assets)
Tier 1 Capital (to average assets), Actual Amount		$ 163,145
Tier 1 Capital (to average assets), Actual Ratio		0.084
Tier 1 Capital (to average assets), Minimum Capital Required, Amount		$ 77,953
Tier 1 Capital (to average assets), Minimum Capital Required, Ratio		0.040
Tier 1 Capital (to average assets), Required to be Well Capitalized, Amount		$ 97,441
Tier 1 Capital (to average assets), Required to be Well Capitalized, Ratio		0.050
Subsidiaries
Banking Regulation, Total Capital [Abstract]
Total Capital (to risk-weighted assets), Actual Amount	$ 736,099	$ 219,976
Total Capital (to risk-weighted assets), Actual Ratio	0.136	0.148
Total Capital (to risk-weighted assets), Minimum Capital Required, Amount	$ 567,793	$ 156,631
Total Capital (to risk-weighted assets), Minimum Capital Required, Ratio	0.105	0.105
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Amount	$ 540,755	$ 149,172
Total Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio	0.100	0.100
Common Equity Tier 1 Capital (To Risk-weighted Assets)
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Amount	$ 685,956	$ 207,632
Common Equity Tier 1 Capital (to risk-weighted assets), Actual Ratio	0.127	0.139
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount	$ 378,529	$ 104,421
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio	7.00%	7.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount	$ 351,491	$ 96,962
Common Equity Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio	6.50%	6.50%
Tier 1 Capital (To Risk-weighted Assets)
Tier 1 Capital (to risk-weighted assets), Actual Amount	$ 685,956	$ 207,632
Tier 1 Capital (to risk-weighted assets), Actual Ratio	0.127	0.139
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Amount	$ 459,642	$ 126,797
Tier 1 Capital (to risk-weighted assets), Minimum Capital Required, Ratio	0.085	0.085
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Amount	$ 432,604	$ 119,338
Tier 1 Capital (to risk-weighted assets), Required to be Well Capitalized, Ratio	0.080	0.080
Tier 1 Leverage Capital (To Average Assets)
Tier 1 Capital (to average assets), Actual Amount	$ 685,956	$ 207,632
Tier 1 Capital (to average assets), Actual Ratio	0.088	0.084
Tier 1 Capital (to average assets), Minimum Capital Required, Amount	$ 312,057	$ 99,000
Tier 1 Capital (to average assets), Minimum Capital Required, Ratio	0.040	0.040
Tier 1 Capital (to average assets), Required to be Well Capitalized, Amount	$ 390,071	$ 123,751
Tier 1 Capital (to average assets), Required to be Well Capitalized, Ratio	0.050	0.050