Annual report pursuant to Section 13 and 15(d)

Note 1 - Summary of Significant Accounting Policies (Details Textual)

v3.22.1
Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($)
12 Months Ended
Jan. 18, 2022
Dec. 31, 2021
Dec. 31, 2020
Federal Home Loan Bank Stock   $ 550,000 $ 512,000
Unrecognized Tax Benefits, Ending Balance   $ 0 $ 0
First Mortgage Loans [Member] | One To Four Family Residential [Member]      
Financing Receivable, Minimum Percentage of Loan-to-value Ratio, Requires Mortgage Insurance   80.00%  
First Mortgage Loans [Member] | Multifamily and Commercial Real Estate [Member]      
Financing Receivable, Maximum Term (Year)   30 years  
Financing Receivable, Maximum Loan-to-value Ratio   75.00%  
Stock Offering [Member]      
Proceeds from Future Issuance of Stock, Held in Deposit   $ 87,300,000  
Subscription Offering [Member] | Subsequent Event [Member]      
Stock Issued During Period, Shares, New Issues (in shares) 5,290,000    
Shares Issued, Price Per Share (in dollars per share) $ 10.00    
Proceeds from Issuance of Common Stock $ 53,000,000.0    
Subscription Offering [Member] | Subsequent Event [Member] | NSTS Charitable Foundation [Member]      
Payments of Charitable Contributions $ 150,000    
Subscription Offering [Member] | Subsequent Event [Member] | NSTS Charitable Foundation [Member] | Contribution of Nonmonetary Assets to Charitable Organization [Member]      
Stock Issued During Period, Shares, New Issues (in shares) 107,959