XML 96 R81.htm IDEA: XBRL DOCUMENT v3.20.4
Note 9 - Employee Retirement Plans - Assumptions of Net Periodic Costs (Details) - Pension Plan [Member]
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Discount rate 3.50% 4.50%
Expected long-term rate of return on assets 4.00% 4.00%
Rates of annual increase in compensation levels 2.30% 2.80%