FAIR VALUE MEASUREMENTS - Schedule of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
ASSETS:
Cash and cash equivalents	$ 338,489	$ 409,632
Available for sale securities	50,582	77,356
Derivative financial instruments		58
Contingent consideration		762
Total assets	389,071	487,808
LIABILITIES:
Contingent purchase consideration	(1,748)
Derivative financial instruments	(49)	(68)
Total liabilities	(1,797)	(68)
U.S. government and municipal obligations
ASSETS:
Available for sale securities	31,341	27,622
Commercial paper
ASSETS:
Available for sale securities	14,644	48,722
Corporate bonds
ASSETS:
Available for sale securities	4,597	1,012
Level 1
ASSETS:
Cash and cash equivalents	338,489	409,632
Derivative financial instruments		0
Contingent consideration		0
Total assets	374,427	421,376
LIABILITIES:
Contingent purchase consideration	0
Derivative financial instruments	0	0
Total liabilities	0	0
Level 1 \| U.S. government and municipal obligations
ASSETS:
Available for sale securities	31,341	10,732
Level 1 \| Commercial paper
ASSETS:
Available for sale securities	0	0
Level 1 \| Corporate bonds
ASSETS:
Available for sale securities	4,597	1,012
Level 2
ASSETS:
Cash and cash equivalents	0	0
Derivative financial instruments		58
Contingent consideration		0
Total assets	14,644	65,670
LIABILITIES:
Contingent purchase consideration	0
Derivative financial instruments	(49)	(68)
Total liabilities	(49)	(68)
Level 2 \| U.S. government and municipal obligations
ASSETS:
Available for sale securities	0	16,890
Level 2 \| Commercial paper
ASSETS:
Available for sale securities	14,644	48,722
Level 2 \| Corporate bonds
ASSETS:
Available for sale securities	0	0
Level 3
ASSETS:
Cash and cash equivalents	0	0
Derivative financial instruments		0
Contingent consideration		762
Total assets	0	762
LIABILITIES:
Contingent purchase consideration	(1,748)
Derivative financial instruments	0	0
Total liabilities	(1,748)	0
Level 3 \| U.S. government and municipal obligations
ASSETS:
Available for sale securities	0	0
Level 3 \| Commercial paper
ASSETS:
Available for sale securities	0	0
Level 3 \| Corporate bonds
ASSETS:
Available for sale securities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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