Note 13 - Employee Benefit Plans - Pension Plan Assets Measured and Recorded at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair value of plan assets	$ 11,316	$ 10,599	$ 9,482
Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	11,316	10,599
Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets
Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets
Money Market Funds [Member]
Fair value of plan assets	143	385
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	143	385
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets
Mutual Funds, Debt [Member]
Fair value of plan assets	4,518	4,322
Mutual Funds, Debt [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	4,518	4,322
Mutual Funds, Debt [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets
Mutual Funds, Debt [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets
Mutual Funds, Equity [Member]
Fair value of plan assets	5,798	4,981
Mutual Funds, Equity [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	5,798	4,981
Mutual Funds, Equity [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets
Mutual Funds, Equity [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets
Emclaire Stock [Member]
Fair value of plan assets	857	911
Emclaire Stock [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	857	911
Emclaire Stock [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets
Emclaire Stock [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets