5. FINANCIAL INSTRUMENTS (Details 2) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Available-for-sale investments
Fair Value	$ 68,231,000
Other information
Maximum maturity period of investment portfolio	3 years
Deferred tax liability related to unrecognized gains and losses on short-term and long-term investments	11,000	14,000
Short-term investments
Available-for-sale investments
Cost	39,386,000	26,096,000
Gross Unrealized Gains	26,000	43,000
Fair Value	39,412,000	26,139,000
Short-term investments | State and municipal obligations
Available-for-sale investments
Cost	8,336,000	10,564,000
Gross Unrealized Gains	4,000	17,000
Fair Value	8,340,000	10,581,000
Short-term investments | Corporate notes
Available-for-sale investments
Cost	5,023,000	6,052,000
Gross Unrealized Gains	12,000	14,000
Fair Value	5,035,000	6,066,000
Short-term investments | Agency bonds
Available-for-sale investments
Cost	3,523,000
Gross Unrealized Gains	2,000
Fair Value	3,525,000
Short-term investments | Certificates of deposits
Available-for-sale investments
Cost	14,997,000	9,480,000
Gross Unrealized Gains	6,000	12,000
Fair Value	15,003,000	9,492,000
Short-term investments | Other
Available-for-sale investments
Cost	7,507,000
Gross Unrealized Gains	2,000
Fair Value	7,509,000
Long-term investment
Available-for-sale investments
Cost	28,800,000	35,478,000
Gross Unrealized Gains	26,000	35,000
Gross Unrealized Losses	(7,000)	(18,000)
Fair Value	28,819,000	35,495,000
Long-term investment | State and municipal obligations
Available-for-sale investments
Cost	8,227,000	11,992,000
Gross Unrealized Gains	10,000	3,000
Fair Value	8,237,000	11,995,000
Long-term investment | Corporate notes
Available-for-sale investments
Cost	6,392,000	8,436,000
Gross Unrealized Gains	16,000	14,000
Fair Value	6,408,000	8,450,000
Long-term investment | Agency bonds
Available-for-sale investments
Cost	2,011,000
Gross Unrealized Losses	(5,000)
Fair Value	2,006,000
Long-term investment | Certificates of deposits
Available-for-sale investments
Cost	10,500,000	9,008,000
Gross Unrealized Gains		18,000
Gross Unrealized Losses	(2,000)
Fair Value	10,498,000	9,026,000
Long-term investment | Other
Available-for-sale investments
Cost	1,670,000	6,042,000
Gross Unrealized Losses		(18,000)
Fair Value	$ 1,670,000	$ 6,024,000