Note 11 - Retirement Plans - Target Asset Allocation (Details)	Dec. 31, 2024
Large Cap Blend [Member]
Target range	27.00%
Large Cap Blend [Member] | Minimum [Member]
Target range	0.00%
Large Cap Blend [Member] | Maximum [Member]
Target range	50.00%
Mid-cap Blend [Member]
Target range	10.00%
Mid-cap Blend [Member] | Minimum [Member]
Target range	0.00%
Mid-cap Blend [Member] | Maximum [Member]
Target range	40.00%
Small Cap Blend [Member]
Target range	6.00%
Small Cap Blend [Member] | Minimum [Member]
Target range	0.00%
Small Cap Blend [Member] | Maximum [Member]
Target range	25.00%
Foreign Large Blend [Member]
Target range	11.00%
Foreign Large Blend [Member] | Minimum [Member]
Target range	0.00%
Foreign Large Blend [Member] | Maximum [Member]
Target range	40.00%
Emerging Markets [Member]
Target range	3.00%
Emerging Markets [Member] | Minimum [Member]
Target range	0.00%
Emerging Markets [Member] | Maximum [Member]
Target range	25.00%
Real Estate [Member]
Target range	3.00%
Real Estate [Member] | Minimum [Member]
Target range	0.00%
Real Estate [Member] | Maximum [Member]
Target range	20.00%
US Treasury Securities [Member]
Target range	3.50%
US Treasury Securities [Member] | Minimum [Member]
Target range	0.00%
US Treasury Securities [Member] | Maximum [Member]
Target range	25.00%
Intermediate Core Plus Bond [Member]
Target range	25.00%
Intermediate Core Plus Bond [Member] | Minimum [Member]
Target range	0.00%
Intermediate Core Plus Bond [Member] | Maximum [Member]
Target range	50.00%
Short-term Bond [Member]
Target range	3.00%
Short-term Bond [Member] | Minimum [Member]
Target range	0.00%
Short-term Bond [Member] | Maximum [Member]
Target range	25.00%
Bank Loan [Member]
Target range	0.00%
Bank Loan [Member] | Minimum [Member]
Target range	0.00%
Bank Loan [Member] | Maximum [Member]
Target range	25.00%
High Yield Bond [Member]
Target range	4.00%
High Yield Bond [Member] | Minimum [Member]
Target range	0.00%
High Yield Bond [Member] | Maximum [Member]
Target range	25.00%
Emerging Markets Bond [Member]
Target range	3.00%
Emerging Markets Bond [Member] | Minimum [Member]
Target range	0.00%
Emerging Markets Bond [Member] | Maximum [Member]
Target range	20.00%
Money Market Funds [Member]
Target range	1.50%
Money Market Funds [Member] | Minimum [Member]
Target range	0.00%
Money Market Funds [Member] | Maximum [Member]
Target range	100.00%