Note 10 - Fair Value Accounting and Measurement - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investment securities available for sale, at fair value	$ 353,144	$ 344,212
Sold loan servicing rights	3,865	0
Fair Value, Recurring [Member]
Sold loan servicing rights	3,865
Equity investments	9,952	3,071
Investments, Fair Value Disclosure, Total	366,961	347,283
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Sold loan servicing rights	0
Equity investments	0	0
Investments, Fair Value Disclosure, Total	12,830	11,963
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Sold loan servicing rights	0
Equity investments	9,952	3,071
Investments, Fair Value Disclosure, Total	350,266	335,320
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Sold loan servicing rights	3,865	3,820
Equity investments	0	0
Investments, Fair Value Disclosure, Total	3,865	0
US States and Political Subdivisions Debt Securities [Member]
Investment securities available for sale, at fair value	104,048	113,364
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	104,048	113,364
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	4,979	5,902
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	99,069	107,462
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0	0
US Treasury Securities [Member]
Investment securities available for sale, at fair value	2,420
US Treasury Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	2,420
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	2,420
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0
International Agency Bonds [Member]
Investment securities available for sale, at fair value	1,762	1,920
International Agency Bonds [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		1,920
International Agency Bonds [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		0
International Agency Bonds [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		1,920
International Agency Bonds [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		0
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	1,762
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	1,762
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0
Asset-backed Securities, Issued by Private Enterprises [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		14,489
Asset-backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		0
Asset-backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		14,489
Asset-backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		0
Corporate Debt Securities [Member]
Investment securities available for sale, at fair value	57,977	59,789
Corporate Debt Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	57,977	59,789
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	5,431	6,061
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	52,546	53,728
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities available for sale, at fair value	85,796	79,962
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	85,796	79,962
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	85,796	79,962
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0	0
US Small Business Administration Securities [Member]
Investment securities available for sale, at fair value		14,680
US Small Business Administration Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		14,680
US Small Business Administration Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		0
US Small Business Administration Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		14,680
US Small Business Administration Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value		0
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Investment securities available for sale, at fair value	101,141	60,008
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	101,141	60,008
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	0	0
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	101,141	60,008
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value	$ 0	$ 0