Note 1 - Summary of Significant Accounting Policies (Details Textual)		3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 01, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Number of Operating Segments				2
Retained Earnings (Accumulated Deficit), Ending Balance		$ 375,462,000		$ 375,462,000		$ 353,574,000
Loans and Leases Receivable, Allowance, Impact of Accounting Policy Adoption			$ 0		$ 8,221,000
Off-Balance Sheet, Credit Loss, Liability, Ending Balance	$ 3,850,000						$ 350,000
Loans and Leases Receivable, Net Amount, Total		4,132,584,000		4,132,584,000		3,479,676,000
Goodwill, Impairment Loss		0	$ 0	0	$ 0	$ 0
Restricted Cash and Cash Equivalents, Total		$ 400,000		$ 400,000
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)				3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)				40 years
Transfer of Loans From Purchased Credit Impaired to Purchased Credit Deteriorated [Member]
Loans and Leases Receivable, Net Amount, Total	1,600,000
Accounting Standards Update 2016-13 [Member]
Retained Earnings (Accumulated Deficit), Ending Balance	8,800,000
Loans and Leases Receivable, Allowance, Impact of Accounting Policy Adoption	8,200,000
Off-Balance Sheet, Credit Loss, Liability, Ending Balance	3,500,000
Deferred Tax Assets, Net of Valuation Allowance, Total	$ 2,900,000