INCOME TAXES - Summary of Components of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Deferred tax assets:
Accrued expenses	$ 4,068	$ 4,883
Deferred revenue	12,168	8,427
Reserves	3,375	6,240
Pension and other retiree benefits	5,307	4,978
Net operating loss carryforwards	21,251	27,322
Tax credit carryforwards	6,625	5,502
Share-based compensation	5,164	6,418
Other	418	288
Total gross deferred tax assets	58,376	64,058
Valuation allowance	(3,108)	(3,374)
Net deferred tax assets	55,268	60,684
Deferred tax liabilities:
Intangible assets	(195,959)	(323,008)
Depreciation	(4,187)	(8,695)
Total deferred tax liability	$ (144,878)	$ (271,019)