Note 4 - Loans Receivable and Related Allowance for Loan Losses (Details Textual)	3 Months Ended
Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Loans and Leases Receivable, Deferred Income, Total	$ 2,200,000		$ 2,200,000
Loans and Leases Receivable, Allowance, Ending Balance	6,639,000	$ 5,935,000	6,508,000	$ 6,127,000
Financing Receivable, Troubled Debt Restructuring	459,000		394,000
Allowance for Losses Allocated to Loans Classified as TDRS	$ 7,000		12,000
Financing Receivable, Modifications, Number of Contracts		0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Residential Portfolio Segment [Member]
Loans and Leases Receivable, Allowance, Ending Balance	$ 2,256,000	$ 1,919,000	$ 2,198,000	$ 2,090,000
Financing Receivable, Troubled Debt Restructuring	$ 74,000
Financing Receivable, Modifications, Number of Contracts	1
United American Savings Bank [Member]
Loans and Leases Receivable, Allowance, Ending Balance	$ 0
Northern Hancock Bank & Trust Co. [Member]
Loans and Leases Receivable, Allowance, Ending Balance	0
Community First [Member]
Loans and Leases Receivable, Allowance, Ending Balance	$ 0

Allowance for losses allocated to loans classified as TDRs as at the reporting date

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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