Note O - Employee and Director Benefit Plans - Amounts Recognized in Accumulated Post-Retirement Benefit Obligation and Other Comprehensive Income (Loss) (Details) - Other Postretirement Benefits Plan [Member] $ in Thousands	Dec. 31, 2019 USD ($)
Unrecognized actuarial gain	$ 475
Amortization of prior service cost	(81)
Total accumulated other comprehensive income	$ 394

Note O - Employee and Director Benefit Plans - Amounts Recognized in Accumulated Post-Retirement Benefit Obligation and Other Comprehensive Income (Loss) (Details) - Other Postretirement Benefits Plan [Member]
$ in Thousands

Dec. 31, 2019

USD ($)

$ 475

Amortization of prior service cost

(81)

Total accumulated other comprehensive income

$ 394