FAIR VALUE MEASUREMENTS - Schedule of Financial Assets and Liabilities (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
ASSETS:
Cash and cash equivalents	$ 106,704,000	$ 102,076,000
Marketable securities	134,022,000us-gaap_AvailableForSaleSecurities	116,718,000us-gaap_AvailableForSaleSecurities
Derivative financial instruments	16,000us-gaap_DerivativeAssets	368,000us-gaap_DerivativeAssets
Total assets	240,742,000us-gaap_AssetsFairValueDisclosure	219,162,000us-gaap_AssetsFairValueDisclosure
LIABILITIES:
Contingent purchase consideration	(4,445,000)	(4,291,000)
Contingent contractual non-compliance liability		(49,000)
Derivative financial instruments	(1,223,000)us-gaap_DerivativeLiabilities	(139,000)us-gaap_DerivativeLiabilities
Total liabilities	(5,668,000)us-gaap_LiabilitiesFairValueDisclosure	(4,479,000)us-gaap_LiabilitiesFairValueDisclosure
U.S. government and municipal obligations
ASSETS:
Marketable securities	119,701,000	91,757,000
Commercial paper
ASSETS:
Marketable securities	7,590,000	14,581,000
Corporate bonds
ASSETS:
Marketable securities	6,731,000	10,380,000
Level 1
ASSETS:
Cash and cash equivalents	106,704,000	82,079,000
Derivative financial instruments	0	0
Total assets	153,287,000	114,451,000
LIABILITIES:
Contingent purchase consideration	0	0
Contingent contractual non-compliance liability		0
Derivative financial instruments	0	0
Total liabilities	0	0
Level 1 \| U.S. government and municipal obligations
ASSETS:
Marketable securities	39,852,000	21,992,000
Level 1 \| Commercial paper
ASSETS:
Marketable securities	0	0
Level 1 \| Corporate bonds
ASSETS:
Marketable securities	6,731,000	10,380,000
Level 2
ASSETS:
Cash and cash equivalents	0	19,997,000
Derivative financial instruments	16,000	368,000
Total assets	87,455,000	104,711,000
LIABILITIES:
Contingent purchase consideration	0	0
Contingent contractual non-compliance liability		0
Derivative financial instruments	(1,223,000)	(139,000)
Total liabilities	(1,223,000)	(139,000)
Level 2 \| U.S. government and municipal obligations
ASSETS:
Marketable securities	79,849,000	69,765,000
Level 2 \| Commercial paper
ASSETS:
Marketable securities	7,590,000	14,581,000
Level 2 \| Corporate bonds
ASSETS:
Marketable securities	0	0
Level 3
ASSETS:
Cash and cash equivalents	0	0
Derivative financial instruments	0	0
Total assets	0	0
LIABILITIES:
Contingent purchase consideration	(4,445,000)	(4,291,000)
Contingent contractual non-compliance liability		(49,000)
Derivative financial instruments	0	0
Total liabilities	(4,445,000)	(4,340,000)
Level 3 \| U.S. government and municipal obligations
ASSETS:
Marketable securities	0	0
Level 3 \| Commercial paper
ASSETS:
Marketable securities	0	0
Level 3 \| Corporate bonds
ASSETS:
Marketable securities	$ 0	$ 0

Business acquisition, purchase price allocation, current liabilities, contractual non compliance liability

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