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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Note 1 - Summary of Significant Accounting Policies (Details Textual)		12 Months Ended
	Oct. 11, 2016 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2014 USD ($)
Proceeds from Issuance of Common Stock, Gross	$ 23,800,000
Stock Issued During Period, Shares, New Issues \| shares	2,383,950	2,520	5,250
Shares Issued, Price Per Share \| $ / shares	$ 10
Second-step Conversion, Stock Conversion Ratio	1.1921
Time Deposits, at Carrying Value		$ 1,483,500	$ 250,000
Maximum Revenues Of Customers		$ 5,000,000
Loan and Lease Receviable, Line of Credit Term		1 year
Real Estate Acquired Through Foreclosure		$ 0	$ 0
Mortgage Loans in Process of Foreclosure, Number of Loans		2	1
Mortgage Loans in Process of Foreclosure, Amount		$ 607,268	$ 276,815
Unrecognized Tax Benefits, Ending Balance		$ 0	$ 0
Open Tax Year		2017 2018 2019
Goodwill, Acquired During Period				$ 650,000
Goodwill, Impairment Loss		$ 0
Number of Operating Segments		1
Number of Reportable Segments		1
Core Deposits [Member]
Finite-Lived Intangible Asset, Useful Life				9 years 292 days
U S D A Rural Development Company Loans [Member]
Loan and Lease Receviable Loan Term		4 years
Loan To Value Ratio		100.00%
Percentage Of Loan Guaranteed By U S D A		90.00%
Maximum Borrowing Limit		$ 25,000
Nonresidential Real Estate Portfolio Segment [Member] \| Land Development Loan [Member]
Loan To Value Ratio		70.00%
Residential Portfolio Segment [Member] \| Construction Loans [Member]
Percentage Of Loan Balance To Be Repaid As Lots Sold		80.00%
Minimum [Member]
Loan and Lease Receviable Loan Term		3 years
Minimum [Member] \| Residential Portfolio Segment [Member] \| Construction Loans [Member]
Loan and Lease Receviable Loan Term		270 days
Maximum [Member]
Loan and Lease Receviable Loan Term		5 years
Maximum [Member] \| Nonresidential Real Estate Portfolio Segment [Member] \| Land Development Loan [Member]
Loan and Lease Receviable Loan Term		10 years
Maximum [Member] \| Residential Portfolio Segment [Member] \| Construction Loans [Member]
Loan and Lease Receviable Loan Term		2 years
Ottawa Savings Bancorp MHC [Member]
Cash Acquired from Acquisition	$ 126,000
Unallocated ESOP Shares [Member]
Stock Issued During Period, Shares, New Issues \| shares	190,716