Note 5 - Retirement Plans - Pension Plan Asset Allocation (Details) |
Dec. 31, 2022 |
Dec. 31, 2021 |
|---|---|---|
| Asset allocation percentage | 100.00% | 100.00% |
| Defined Benefit Plan, Equity Securities [Member] | ||
| Asset allocation percentage | 48.00% | 57.00% |
| Defined Benefit Plan, Equity Securities [Member] | Minimum [Member] | ||
| Target Allocation | 20.00% | |
| Defined Benefit Plan, Equity Securities [Member] | Maximum [Member] | ||
| Target Allocation | 30.00% | |
| Defined Benefit Plan, Debt Security [Member] | ||
| Asset allocation percentage | 51.00% | 42.00% |
| Defined Benefit Plan, Debt Security [Member] | Minimum [Member] | ||
| Target Allocation | 70.00% | |
| Defined Benefit Plan, Debt Security [Member] | Maximum [Member] | ||
| Target Allocation | 80.00% | |
| Defined Benefit Plan, Real Estate [Member] | ||
| Asset allocation percentage | 1.00% | 1.00% |
| Defined Benefit Plan, Real Estate [Member] | Minimum [Member] | ||
| Target Allocation | 0.00% | |
| Defined Benefit Plan, Real Estate [Member] | Maximum [Member] | ||
| Target Allocation | 2.00% |