Note 3 - Marketable Securities (Tables)

6 Months Ended

Aug. 27, 2017

Notes Tables

Schedule of Fair Value of Separate Accounts by Major Category of Investment [Table Text Block]

	August 27, 2017
	Total		Level 1		Level 2		Level 3
U.S. Treasury and other government securities	$	151,337	$	151,337	$	-	$	-
U.S. corporate debt securities		51,536		51,536		-		-
Total marketable securities	$	202,873	$	202,873	$	-	$	-

	February 26, 2017
	Total		Level 1		Level 2		Level 3
U.S. Treasury and other government securities	$	111,261	$	111,261	$	-	$	-
U.S. corporate debt securities		24,891		24,891		-		-
Total marketable securities	$	136,152	$	136,152	$	-	$	-

Schedule of Unrealized Loss on Investments [Table Text Block]

	Amortized Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses
August 27, 2017:
U.S. Treasury and other government securities	$	151,941	$	26	$	630
U.S. corporate debt securities		51,665		-		129
Total marketable securities	$	203,606	$	26	$	759
February 26, 2017:
U.S. Treasury and other government securities	$	111,727	$	136	$	602
U.S. corporate debt securities		24,938		1		48
Total marketable securities	$	136,665	$	137	$	650

Investments Classified by Contractual Maturity Date [Table Text Block]

Due in one year or less	$	25,939
Due after one year through five years		176,934
	$	202,873