Note 5 - Goodwill and Intangible Assets (Details Textual) - USD ($)	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	May 01, 2019	Dec. 31, 2018	Dec. 31, 2013	Dec. 31, 1996
Goodwill, Ending Balance	$ 12,513,000	$ 12,513,000	$ 12,513,000	$ 12,593,000	$ 12,826,000		$ 682,000
Finite-lived Intangible Assets, Fair Value Disclosure	3,000,000		3,000,000
Finite-lived Intangible Assets, Valuation Allowance	0		0
Loans Serviced for Others Outstanding Principal Balance	398,000,000		$ 327,000,000
King Bancorp Inc. [Member]
Goodwill, Ending Balance	$ 12,000,000					$ 11,831,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles						1,519,000
King Bancorp Inc. [Member] | Core Deposits [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles						$ 1,500,000
Indiana Bank [Member] | Commercial Banking [Member]
Goodwill, Ending Balance									$ 682,000
THE BANCorp [Member] | Core Deposits [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles								$ 2,500,000