SHAREHOLDERS’ EQUITY AND REGULATORY CAPITAL - Summary of Actual and Required Capital Amounts and Ratios (Details) $ in Thousands	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Orrstown Financial Services, Inc.
Total risk-based capital:
Actual, Amount	$ 574,472	$ 543,170
Actual, Ratio	0.131	0.124
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 459,551	$ 458,593
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.105	0.105
Tier 1 risk-based capital:
Actual, Amount	$ 495,519	$ 445,146
Actual, Ratio	0.113	0.102
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 372,017	$ 371,242
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.085	0.085
Tier 1 common equity risk-based capital:
Actual, Amount	$ 487,649	$ 437,456
Actual, Ratio	11.10%	10.00%
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 306,367	$ 305,728
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	7.00%	7.00%
Tier 1 leverage capital:
Actual, Amount	$ 495,519	$ 445,146
Actual, Ratio	0.093	0.083
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 214,059	$ 215,375
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.040	0.040
Orrstown Bank
Total risk-based capital:
Actual, Amount	$ 566,081	$ 539,929
Actual, Ratio	0.129	0.124
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 459,528	$ 458,609
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.105	0.105
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 437,645	$ 436,770
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.100	0.100
Tier 1 risk-based capital:
Actual, Amount	$ 516,229	$ 490,029
Actual, Ratio	0.118	0.112
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 371,999	$ 371,255
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.085	0.085
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 350,116	$ 349,416
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.080	0.080
Tier 1 common equity risk-based capital:
Actual, Amount	$ 516,229	$ 490,029
Actual, Ratio	11.80%	11.20%
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 306,352	$ 305,739
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	7.00%	7.00%
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 284,469	$ 283,901
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	6.50%	6.50%
Tier 1 leverage capital:
Actual, Amount	$ 516,229	$ 490,029
Actual, Ratio	0.096	0.091
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 214,240	$ 215,375
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.040	0.040
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 267,801	$ 269,219
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.050	0.050