Aggregate number of common shares reserved for future issuance.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average purchase price of capital shares purchased through an employee stock ownership plan.

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No definition available.

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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-Publisher FASB
-Name Accounting Standards Codification
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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- Definition

Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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SHARE-BASED COMPENSATION PLANS - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	May. 31, 2011
Orrstown 2011 Incentive Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved to be issued				381,920
Shares to be issued under employee stock purchase plan	151,445
Orrstown 2011 Incentive Stock Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense on restricted stock awards	$ 237	$ 131
Tax benefits from compensation expense	83	$ 46
Unrecognized compensation expense	$ 2,495		$ 2,293
Unrecognized compensation expense, recognition period	3 years
Orrstown 2011 Incentive Stock Plan \| Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term to exercise option	10 years
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved to be issued	350,000
Shares to be issued under employee stock purchase plan	189,877
Maximum shares purchase, as percentage of salary	10.00%
Percentage of value of the shares on the semi-annual offering	95.00%
Shares purchased by employees	2,461	2,964
Weighted average price (in usd per share)	$ 16.57	$ 15.74
Compensation expense recognized	$ 3	$ 3