Note 3 - Marketable Securities (Tables)

9 Months Ended

Dec. 01, 2019

Notes Tables

Debt Securities, Available-for-sale [Table Text Block]

	December 1, 2019
	Total		Level 1		Level 2		Level 3
U.S. Treasury and other government securities	$	109,491	$	109,491	$	-	$	-
U.S. corporate debt securities		27,995		27,995		-		-
Total marketable securities	$	137,486	$	137,486	$	-	$	-

	March 3, 2019
	Total		Level 1		Level 2		Level 3
U.S. Treasury and other government securities	$	68,718	$	68,718	$	-	$	-
U.S. corporate debt securities		11,899		11,899		-		-
Total marketable securities	$	80,617	$	80,617	$	-	$	-

Schedule of Available-for-sale Securities Reconciliation [Table Text Block]

	Amortized Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses
December 1, 2019:
U.S. Treasury and other government securities	$	109,139	$	440	$	88
U.S. corporate debt securities		27,959		59		23
Total marketable securities	$	137,098	$	499	$	111
March 3, 2019:
U.S. Treasury and other government securities	$	68,727	$	44	$	53
U.S. corporate debt securities		11,924		7		32
Total marketable securities	$	80,651	$	51	$	85

Investments Classified by Contractual Maturity Date [Table Text Block]

Due in one year or less	$	80,787
Due after one year through five years		56,699
	$	137,486