FAIR VALUE OF FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Fair Value Measurements within the Fair Value Hierarchy (Details) - Fair value measurements on recurring basis - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023
Fair value of assets and liabilities
Cash and Cash Equivalents	$ 470,773	$ 464,448
Short-Term Investments	33,099	32,807
Other Current Assets	12,808	12,110
Total assets	516,680	509,365
Cash
Fair value of assets and liabilities
Cash and Cash Equivalents	28,113	22,603
Short-Term Investments	0	0
Other Current Assets	0	0
Total assets	28,113	22,603
Level 1 | Money market funds
Fair value of assets and liabilities
Cash and Cash Equivalents	442,660	439,853
Short-Term Investments	0	0
Other Current Assets	0	0
Total assets	442,660	439,853
Level 1 | Assets of non-qualified retirement plan
Fair value of assets and liabilities
Cash and Cash Equivalents	0	0
Short-Term Investments	0	0
Other Current Assets	12,808	12,110
Total assets	12,808	12,110
Level 1 | U.S. Treasury securities
Fair value of assets and liabilities
Cash and Cash Equivalents	0
Short-Term Investments	25,599
Other Current Assets	0
Total assets	25,599
Level 1 | Certificates of deposit
Fair value of assets and liabilities
Cash and Cash Equivalents	0	0
Short-Term Investments	7,500	7,500
Other Current Assets	0	0
Total assets	$ 7,500	7,500
Level 2 | U.S. Treasury securities
Fair value of assets and liabilities
Cash and Cash Equivalents		1,992
Short-Term Investments		25,307
Other Current Assets		0
Total assets		$ 27,299