Note 12 - Subordinated Notes (Details) $ in Thousands			12 Months Ended
	Aug. 15, 2019	Feb. 12, 2019 USD ($)	Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($)
Subordinated Borrowing [Line Items]
Market Value Discount per ASC 805Market Value Discount per ASC 805			$ (1,606)	$ (218)
Total Subordinated Debentures			68,394	4,782
Gross proceeds		$ 65,000
Net proceeds after deducting underwriting discount and estimated expenses		$ 63,400	63,393
Fixed rate		5.375%
Fixed term	5 years
Unamortized debt issuance costs			1,600
Subordinated debenture dated 2/1/19 [Member]
Subordinated Borrowing [Line Items]
Total Subordinated Debentures			$ 65,000
Interest Rate			5.375%
Subordinated debenture dated 4/30/16 [Member]
Subordinated Borrowing [Line Items]
Total Subordinated Debentures			$ 2,000	$ 2,000
Interest Rate			4.00%	4.00%
Subordinated debenture dated 9/15/16 [Member]
Subordinated Borrowing [Line Items]
Total Subordinated Debentures			$ 3,000	$ 3,000
Interest Rate			4.00%	4.00%
Revolving line of credit
Subordinated Borrowing [Line Items]
Retirement of subordinated debt			$ 21,300
Outstanding amount line of credit			$ 0
Springfield Bancshares
Subordinated Borrowing [Line Items]
Number of subordinated debentures assumed | item			2
Subordinated debentures fixed			5 years
Debentures may be called after a minimum			5 years
London Interbank Offered Rate (LIBOR)
Subordinated Borrowing [Line Items]
Basis points		282.00%
London Interbank Offered Rate (LIBOR) | Revolving line of credit
Subordinated Borrowing [Line Items]
Basis points			2.25%
Subordinated debentures
Subordinated Borrowing [Line Items]
Fair value of subordinated debentures			$ 4,800
Subordinated debentures | Revolving line of credit
Subordinated Borrowing [Line Items]
Outstanding amount line of credit			$ 9,000