Note 4 - Fair Value (Tables)

6 Months Ended

Sep. 30, 2016

Notes Tables

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	September 30, 2016 (1)						March 31, 2016 (1)
			Fair Value Measured at						Fair Value Measured at
			Reporting Date Using						Reporting Date Using
Description	Total		Level 1		Level 2		Total		Level 1		Level 2
	(unaudited)						(unaudited)
Money market funds (2)	$	77,929	$	77,929	$	-	$	115,974	$	115,974	$	-
Marketable equity securities (3)		1,153		1,153		-		1,749		1,749		-
Auction rate preferred securities (3)		350		-		350		350		-		350
Total Assets Measured at Fair Value	$	79,432	$	79,082	$	350	$	118,073	$	117,723	$	350