Note B - Adoption of New Accounting Pronouncements - Remaining Performance Obligations 2 (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 3,005
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year
Revenue, Remaining Performance Obligation, Amount	$ 318
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-03-30
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year
Revenue, Remaining Performance Obligation, Amount	$ 309
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-03-29
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year
Revenue, Remaining Performance Obligation, Amount	$ 299
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-03-28
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year
Revenue, Remaining Performance Obligation, Amount	$ 262
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-03-27
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year
Revenue, Remaining Performance Obligation, Amount	$ 248
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-03-26
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)
Revenue, Remaining Performance Obligation, Amount	$ 1,569