ORRSTOWN FINANCIAL SERVICES, INC. (PARENT COMPANY ONLY) FINANCIAL INFORMATION - Condensed Balance Sheets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Assets
Cash in Orrstown Bank	$ 18,174us-gaap_CashAndDueFromBanks	$ 12,995us-gaap_CashAndDueFromBanks
Securities available for sale	376,199us-gaap_AvailableForSaleSecurities	406,943us-gaap_AvailableForSaleSecurities
Other assets	26,171us-gaap_OtherAssets	15,067us-gaap_OtherAssets
Total assets	1,190,443us-gaap_Assets	1,177,812us-gaap_Assets
Liabilities	1,063,178us-gaap_Liabilities	1,086,373us-gaap_Liabilities
Shareholders’ Equity
Common stock	430us-gaap_CommonStockValue	422us-gaap_CommonStockValue
Additional paid—in capital	123,392us-gaap_AdditionalPaidInCapital	123,105us-gaap_AdditionalPaidInCapital
Retained earnings	1,887	(27,255)
Accumulated other comprehensive income	1,576	(4,813)
Treasury stock	(20)us-gaap_TreasuryStockValue	(20)us-gaap_TreasuryStockValue
Total shareholders’ equity	127,265us-gaap_StockholdersEquity	91,439us-gaap_StockholdersEquity	87,694us-gaap_StockholdersEquity	128,197us-gaap_StockholdersEquity
Total liabilities and shareholders’ equity	1,190,443	1,177,812
Parent Company [Member]
Assets
Cash in Orrstown Bank	389	1,504
Securities available for sale	67	69
Investment in Orrstown Bank	126,084	89,601
Other assets	797	369
Total assets	127,337	91,543
Liabilities	72	104
Shareholders’ Equity
Common stock	430	422
Additional paid—in capital	123,392	123,105
Retained earnings	1,887	(27,255)
Accumulated other comprehensive income	1,576	(4,813)
Treasury stock	(20)	(20)
Total shareholders’ equity	127,265	91,439
Total liabilities and shareholders’ equity	$ 127,337	$ 91,543

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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