Note 2 - Marketable Securities (Tables)

12 Months Ended

Feb. 26, 2017

Notes Tables

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

	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	$	-	$	-

	February 28, 2016
	Total		Level 1		Level 2		Level 3
U.S. Treasury and other government securities	$	118,194	$	118,194	$	-	$	-
U.S. corporate debt securities		21,474		21,474		-		-
Total marketable securities	$	139,668	$	139,668	$	-	$	-

Schedule of Unrealized Loss on Investments [Table Text Block]

	Amortized Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses
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
February 28, 2016:
U.S. Treasury and other government securities	$	117,897	$	372	$	74
U.S. corporate debt securities		21,554		-		81
Total marketable securities	$	139,451	$	372	$	155

Realized Gain (Loss) on Investments [Table Text Block]

	Fiscal Year
	2017		2016		2015
Gross realized gains on sale	$	-	$	-	$	17
Gross realized losses on sale	$	-	$	-	$	44

Investments Classified by Contractual Maturity Date [Table Text Block]

Due in one year or less	$	53,250
Due after one year through five years		82,902
	$	136,152