Note O - Line of Credit and Commercial Letters of Credit	12 Months Ended
Dec. 31, 2020
Notes to Financial Statements
Short-term Debt [Text Block]	O. LINE OF CREDIT AND COMMERCIAL LETTERS OF CREDIT The Company maintains an unsecured line of credit for short term operating cash needs of $5,000,000 as of December 31, 2020. There were no amounts outstanding under this line of credit, which expires September 30, 2021. The interest rate on the line of credit is reset monthly to the London Inter-Bank Offered Rate (LIBOR) plus one half of one percent. In addition, the Company had issued commercial letters of credit totaling $1,247,000 as of both December 31, 2020 and 2019, related to performance on certain customer contracts. As of December 31, 2020, the entire balance of the issued letters of credit had not been drawn upon.

Note O - Line of Credit and Commercial Letters of Credit

12 Months Ended

Dec. 31, 2020

O. LINE OF CREDIT AND COMMERCIAL LETTERS OF CREDIT

The Company maintains an unsecured line of credit for short term operating cash needs of $5,000,000 as of December 31, 2020. There were no amounts outstanding under this line of credit, which expires September 30, 2021. The interest rate on the line of credit is reset monthly to the London Inter-Bank Offered Rate (LIBOR) plus one half of one percent. In addition, the Company had issued commercial letters of credit totaling $1,247,000 as of both December 31, 2020 and 2019, related to performance on certain customer contracts. As of December 31, 2020, the entire balance of the issued letters of credit had not been drawn upon.