Note 2 - Changes to Previously Reported Allowance for Credit Losses (Details Textual) - USD ($)	3 Months Ended				6 Months Ended	9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Jan. 01, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Net Income (Loss) Attributable to Parent, Total	$ 1,553,000	$ 3,993,000	$ 6,235,000	$ 6,096,000	$ 10,228,000	$ 11,781,000	$ 19,098,000
Earnings Per Share, Diluted, Total (in dollars per share)	$ 0.01	$ 0.05	$ 0.08	$ 0.08	$ 0.13	$ 0.14	$ 0.25
Retained Earnings (Accumulated Deficit), Total	$ 19,601,000	$ 18,692,000	$ 15,343,000		$ 18,692,000	$ 19,601,000			$ 13,591,000
Financing Receivable, Credit Loss, Expense (Reversal)	3,998,000	830,000	(72,000)	$ 900,000	758,000	4,756,000	$ 3,900,000
Financing Receivable, Allowance for Credit Loss, Ending Balance	$ 25,255,000	20,997,000	23,156,000	$ 17,218,000	20,997,000	$ 25,255,000	$ 17,218,000		18,964,000	$ 16,110,000	$ 12,975,000
Off-balance Sheet Commitments [Member]
Financing Receivable, Credit Loss, Expense (Reversal)		(18,000)	(74,000)		(92,000)
Financing Receivable, Allowance for Credit Loss, Ending Balance		505,000	523,000		505,000
Revision of Prior Period, Accounting Standards Update, Adjustment [Member]
Net Income (Loss) Attributable to Parent, Total		$ (505,000)	$ 116,000		$ (389,000)
Earnings Per Share, Diluted, Total (in dollars per share)		$ (0.01)	$ 0		$ (0.01)
Retained Earnings (Accumulated Deficit), Total		$ (1,782,000)			$ (1,782,000)			$ 3,600,000
Financing Receivable, Credit Loss, Expense (Reversal)		1,210,000	$ (692,000)		518,000
Financing Receivable, Allowance for Credit Loss, Ending Balance		1,870,000	642,000		1,870,000			1,260,000	0
Revision of Prior Period, Accounting Standards Update, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Retained Earnings (Accumulated Deficit), Total			(1,277,000)
Financing Receivable, Allowance for Credit Loss, Ending Balance								4,200,000
Previously Reported [Member]
Net Income (Loss) Attributable to Parent, Total		$ 4,498,000	$ 6,119,000		$ 10,617,000
Earnings Per Share, Diluted, Total (in dollars per share)		$ 0.06	$ 0.08		$ 0.14
Retained Earnings (Accumulated Deficit), Total		$ 20,474,000			$ 20,474,000
Financing Receivable, Credit Loss, Expense (Reversal)		(380,000)	$ 620,000		240,000
Financing Receivable, Allowance for Credit Loss, Ending Balance		$ 19,127,000	22,514,000		$ 19,127,000			21,944,000	$ 18,964,000
Previously Reported [Member] | Accounting Standards Update 2016-13 [Member]
Retained Earnings (Accumulated Deficit), Total			$ 16,620,000					2,200,000
Financing Receivable, Allowance for Credit Loss, Ending Balance								$ 3,000,000.0