SHAREHOLDERS’ EQUITY AND REGULATORY CAPITAL - Schedule of Actual and Required Capital Amounts and Ratios (Detail) $ in Thousands	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Orrstown Financial Services, Inc.
Total risk-based capital:
Actual, Amount	$ 543,170	$ 326,878
Actual, Ratio	0.124	0.130
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 458,593	$ 264,019
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.105	0.105
Tier 1 risk-based capital:
Actual, Amount	$ 445,146	$ 272,677
Actual, Ratio	0.102	0.108
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 371,242	$ 213,730
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.085	0.085
Tier 1 common equity risk-based capital:
Actual, Amount	$ 437,456	$ 272,677
Actual, Ratio	10.00%	10.80%
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 305,728	$ 176,013
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	7.00%	7.00%
Tier 1 leverage capital:
Actual, Amount	$ 445,146	$ 272,677
Actual, Ratio	0.083	0.089
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 215,375	$ 122,907
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.040	0.040
Orrstown Bank
Total risk-based capital:
Actual, Amount	$ 539,929	$ 320,687
Actual, Ratio	0.124	0.128
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 458,609	$ 263,942
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.105	0.105
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 436,770	$ 251,373
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.100	0.100
Tier 1 risk-based capital:
Actual, Amount	$ 490,029	$ 292,160
Actual, Ratio	0.112	0.116
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 371,255	$ 213,667
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.085	0.085
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 349,416	$ 201,099
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.080	0.080
Tier 1 common equity risk-based capital:
Actual, Amount	$ 490,029	$ 292,160
Actual, Ratio	11.20%	11.60%
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 305,739	$ 175,961
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	7.00%	7.00%
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 283,901	$ 163,393
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	6.50%	6.50%
Tier 1 leverage capital:
Actual, Amount	$ 490,029	$ 292,160
Actual, Ratio	0.091	0.095
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Amount	$ 215,375	$ 122,907
For Capital Adequacy Purposes (includes applicable capital conservation buffer), Ratio	0.040	0.040
To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 269,219	$ 153,634
To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.050	0.050