Note 1 - Nature of Operations and Summary of Significant Accounting Policies (Details Textual)				6 Months Ended
	May 13, 2016 USD ($) $ / shares	Sep. 11, 2015 USD ($)	Oct. 10, 2012 USD ($) $ / shares shares	Sep. 30, 2018 shares	Jun. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2018 shares	Apr. 15, 2015 $ / shares
Common Stock, Shares, Issued, Total | shares			3,703,000	3,416,414		3,407,613
Share Price | $ / shares			$ 10
Proceeds from Issuance of Common Stock			$ 35,580,000
Noninterest Expense Offering Cost			$ 1,450,000
Employee Stock Option Plan, Subscribed Percentage			8.00%
Employee Stock Ownership Plan (ESOP), Number of Allocated Shares | shares			296,240
Number of Branches				7
Core Deposits [Member]
Finite-Lived Intangible Asset, Useful Life				8 years
Merger With Orrstown Financial Services [Member] | Scenario, Forecast [Member]
Merger Termination Fee Amount					$ 2,200,000
Merger With Orrstown Financial Services [Member] | Orrstown Financial Services, Inc. [Member] | Scenario, Forecast [Member]
Business Acquisition, Share Price | $ / shares					$ 4.10
Business Acquisition, Equity Interest Issued or Issuable, Shares Available for Issuance Upon Conversion of Acquiree Stock | shares					0.54
Fraternity Community Bancorp, Inc. [Member]
Business Acquisition, Share Price | $ / shares	$ 19.25
Payments to Acquire Businesses, Gross	$ 25,700,000
Fairmount Bancorp, Inc. [Member]
Business Acquisition, Share Price | $ / shares							$ 30
Business Combination, Consideration Transferred, Total		$ 15,400,000