INVESTMENTS (Details) - USD ($)	Dec. 31, 2016	Mar. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 6,684,000	$ 7,037,000
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	(20,000)	(12,000)
Fair Value	6,664,000	7,025,000
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	67,365,000	56,907,000
Gross Unrecognized Gain	1,000	3,000
Gross Unrecognized (Loss)	(233,000)	(123,000)
Fair Value, Total investments	67,133,000	56,787,000
Available-for-sale securities and Held-to-maturity securities [Abstract]
Unrealized loss on available-for-sale investments, net of related income taxes	(11,000)	(7,000)
Available-for-sale investments by stated maturity, amortized cost [Abstract]
Amortized Cost, Due in less than one year	5,057,000	4,314,000
Amortized Cost, Due in 1 to 4 years	1,627,000	2,723,000
Amortized Cost	6,684,000	7,037,000
Available-for-sale investments by stated maturity, fair value [Abstract]
Fair Value, Due in less than one year	5,044,000	4,311,000
Fair Value, Due in 1 to 4 years	1,620,000	2,714,000
Fair Value, Total investments	6,664,000	7,025,000
Held-to-maturity investments by stated maturity, amortized cost [Abstract]
Amortized Cost, Due in less than one year	47,247,000	37,163,000
Amortized Cost, Due in 1 to 4 years	20,118,000	19,744,000
Amortized Cost, Total investments	67,365,000	56,907,000
Held-to-maturity investments by stated maturity, fair value [Abstract]
Fair Value, Due in less than one year	47,186,000	37,128,000
Fair Value, Due in 1 to 4 years	19,947,000	19,659,000
Fair Value, Total investments	67,133,000	56,787,000
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,684,000	7,037,000
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	(20,000)	(12,000)
Fair Value	6,664,000	7,025,000
Available-for-sale investments by stated maturity, amortized cost [Abstract]
Amortized Cost	6,684,000	7,037,000
Certificates of Deposit [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	498,000	2,737,000
Gross Unrecognized Gain	0	3,000
Gross Unrecognized (Loss)	0	0
Fair Value, Total investments	498,000	2,740,000
Held-to-maturity investments by stated maturity, fair value [Abstract]
Fair Value, Total investments	498,000	2,740,000
Commercial Paper [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	8,580,000	12,455,000
Gross Unrecognized Gain	1,000	0
Gross Unrecognized (Loss)	(4,000)	(6,000)
Fair Value, Total investments	8,577,000	12,449,000
Held-to-maturity investments by stated maturity, fair value [Abstract]
Fair Value, Total investments	8,577,000	12,449,000
Corporate Bonds [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	58,287,000	41,715,000
Gross Unrecognized Gain	0	0
Gross Unrecognized (Loss)	(229,000)	(117,000)
Fair Value, Total investments	58,058,000	41,598,000
Held-to-maturity investments by stated maturity, fair value [Abstract]
Fair Value, Total investments	$ 58,058,000	$ 41,598,000