Note 6 - Leases - Undiscounted Future Lease Payments Under Operating Leases and Financial Leases (Details) - USD ($) $ in Thousands	Dec. 26, 2020	Mar. 31, 2020	Dec. 28, 2019
Balance of 2021, operating	$ 4,106
Balance of 2021, financing	1,886
2022, operating	19,398
2022, financing	7,544
2023, operating	13,926
2023, financing	7,544
2024, operating	7,006
2024, financing	6,016
2025, operating	3,485
2025, financing	2,662
2026-2032, operating	4,720
2026-2032, financing	4,266
Total minimum payment required, operating	52,641
Total minimum payment required, financing	29,918
Less interest, operating	3,878
Less interest, financing	2,764
Present value of minimum lease payments, operating	48,763
Present value of minimum lease payments, financing	27,154
Amount due within one year, operating	18,327	$ 21,550	$ 24,430
Amount due within one year, financing	6,608	6,224	6,584
Long-term lease obligations	30,436	42,760	47,965
Long-term lease obligations	20,546	$ 24,366	$ 27,007
Current Portion of Long-term Debt and Lease Obligations [Member]
Amount due within one year, operating	$ 18,327