DEFERRED COMPENSATION (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Bank deposits held	$ 280,293	$ 301,970	$ 242,461	$ 235,266
Short-term investments [Member] | Mutual funds [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Investments	14,600	12,400
Other long-term liabilities [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation liability, noncurrent	15,900	13,700
Bank Time Deposits [Member] | Cash and cash equivalents [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Bank deposits held	$ 800	$ 800