Note 4 - Loans Receivable and Related Allowance for Loan Losses (Details Textual)	3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Loans and Leases Receivable, Deferred Income, Total	$ 1,800,000			$ 1,800,000		$ 2,500,000
Loans and Leases Receivable, Net of Deferred Income, Total	804,139,000			804,139,000		809,918,000
Loans and Leases Receivable, Allowance, Ending Balance	9,848,000	$ 8,159,000		9,848,000	$ 8,159,000	9,580,000	$ 9,685,000	$ 7,220,000	$ 6,556,000
Financing Receivable, Troubled Debt Restructuring	372,000			372,000		396,000
Allowance for Losses Allocated to Loans Classified as TDRS	$ 0			$ 0		$ 6,000
Financing Receivable, Modifications, Number of Contracts	0	0		0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0		0	0
Financing Receivable, Number of Payment Deferrals	15			15		419
Financing Receivable, Principal and Interest Deferred Payments	$ 25,300,000			$ 25,300,000		$ 111,600,000
Financing Receivable, Percent of Outstanding Loan Balance Deferred	3.10%			3.10%		14.70%
Financing Receivable, Number of Interest Only Payment Deferrals	9			9
Financing Receivable, Interest Only Deferred Payments	$ 17,600,000			$ 17,600,000
Financing Receivable, Percent of Interest Only Deferred Payments	69.60%			69.60%
Hospitality Loans [Member]
Financing Receivable, Percent of Outstanding Loan Balance Deferred	100.00%			100.00%
United American Savings Bank [Member]
Loans and Leases Receivable, Allowance, Ending Balance	$ 0			$ 0
Other Loans [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	131,708,000			131,708,000		$ 129,174,000
Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	85,622,000			85,622,000		89,139,000
Loans and Leases Receivable, Allowance, Ending Balance	675,000	$ 803,000		675,000	$ 803,000	677,000	$ 612,000	$ 681,000	$ 636,000
Commercial Portfolio Segment [Member] | Other Loans [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	85,622,000			85,622,000		89,139,000
Commercial Portfolio Segment [Member] | SBA CARES Act Paycheck Protection Program [Member] | Other Loans [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	28,500,000			28,500,000		30,400,000
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums, Total	$ 3,700,000			3,700,000
Amortization of Deferred Loan Origination Fees, Net				$ 924,000,000,000		$ 1,300,000
Commercial Portfolio Segment [Member] | SBA CARES Act Paycheck Protection Program [Member] | Other Loans [Member] | Forecast [Member]
Amortization of Deferred Loan Origination Fees, Net			$ 1,500,000