v3.26.3
Regulatory Capital Requirements (Details)
$ in Thousands
Sep. 30, 2026
USD ($)
Dec. 31, 2025
USD ($)
Total Capital (to Risk-Weighted Assets)    
Total Capital (to Risk-Weighted Assets), Actual Amount $ 893,757 $ 871,043
Total Capital (to Risk-Weighted Assets), Actual Ratio 0.124 0.136
Total Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Amount $ 575,546 $ 512,904
Total Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Ratio 0.08 0.08
Total Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Amount $ 719,432 $ 641,130
Total Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.10 0.10
Tier I Capital (to Risk-Weighted Assets)    
Tier I Capital (to Risk-Weighted Assets), Actual Amount $ 837,727 $ 822,626
Tier I Capital (to Risk-Weighted Assets), Actual Ratio 0.116 0.128
Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Amount $ 431,659 $ 384,678
Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Ratio 0.06 0.06
Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Amount $ 575,546 $ 512,904
Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.08 0.08
Common Equity Tier I Capital (to Risk-Weighted Assets)    
Common Equity Tier I Capital (to Risk-Weighted Assets), Actual Amount $ 837,727 $ 822,626
Common Equity Tier I Capital (to Risk-Weighted Assets), Actual Ratio 0.116 0.128
Common Equity Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Amount $ 323,745 $ 288,508
Common Equity Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Ratio 0.045 0.045
Common Equity Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Amount $ 467,631 $ 416,734
Common Equity Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.065 0.065
Tier I Capital (to Total Average Assets)    
Tier I Capital (to Total Average Assets), Actual Amount $ 837,727 $ 822,626
Tier I Capital (to Total Average Assets), Actual Ratio 0.113 0.133
Tier I Capital (to Total Average Assets), For minimum capital adequacy purposes, Amount $ 297,833 $ 247,709
Tier I Capital (to Total Average Assets), For minimum capital adequacy purposes, Ratio 0.04 0.04
Tier I Capital (to Total Average Assets), To be well capitalized under prompt corrective action provisions, Amount $ 372,291 $ 309,636
Tier I Capital (to Total Average Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.05 0.05
Needham Bank    
Total Capital (to Risk-Weighted Assets)    
Total Capital (to Risk-Weighted Assets), Actual Amount $ 862,549 $ 791,298
Total Capital (to Risk-Weighted Assets), Actual Ratio 0.12 0.124
Total Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Amount $ 574,857 $ 511,589
Total Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Ratio 0.08 0.08
Total Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Amount $ 718,571 $ 639,486
Total Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.10 0.10
Tier I Capital (to Risk-Weighted Assets)    
Tier I Capital (to Risk-Weighted Assets), Actual Amount $ 806,519 $ 742,881
Tier I Capital (to Risk-Weighted Assets), Actual Ratio 0.112 0.116
Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Amount $ 431,143 $ 383,692
Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Ratio 0.06 0.06
Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Amount $ 574,857 $ 511,589
Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.08 0.08
Common Equity Tier I Capital (to Risk-Weighted Assets)    
Common Equity Tier I Capital (to Risk-Weighted Assets), Actual Amount $ 806,519 $ 742,881
Common Equity Tier I Capital (to Risk-Weighted Assets), Actual Ratio 0.112 0.116
Common Equity Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Amount $ 323,357 $ 287,769
Common Equity Tier I Capital (to Risk-Weighted Assets), For minimum capital adequacy purposes, Ratio 0.045 0.045
Common Equity Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Amount $ 467,071 $ 415,666
Common Equity Tier I Capital (to Risk-Weighted Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.065 0.065
Tier I Capital (to Total Average Assets)    
Tier I Capital (to Total Average Assets), Actual Amount $ 806,519 $ 742,881
Tier I Capital (to Total Average Assets), Actual Ratio 0.109 0.122
Tier I Capital (to Total Average Assets), For minimum capital adequacy purposes, Amount $ 296,606 $ 244,395
Tier I Capital (to Total Average Assets), For minimum capital adequacy purposes, Ratio 0.04 0.04
Tier I Capital (to Total Average Assets), To be well capitalized under prompt corrective action provisions, Amount $ 370,757 $ 305,494
Tier I Capital (to Total Average Assets), To be well capitalized under prompt corrective action provisions, Ratio 0.05 0.05