RESTRUCTURING, IMPAIRMENT AND OTHER CHARGES - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended			24 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($) leasedOfficeSpace	Mar. 31, 2021 USD ($)	Mar. 31, 2024 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	$ 397	$ 1,383	$ 575	$ 1,471
Number of leased office space exited | leasedOfficeSpace						8
ROU asset group impairments and adjustments	0	$ 1,918	0	$ 1,946	$ 26,500	$ 26,500
Operating lease, ROU asset, impairment loss								$ 22,200
Leasehold improvements					4,300			$ 4,300
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			600		4,200		$ 1,700
Employee Severance | Restructuring Activity 2025
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	300		300
Employee Severance | Restructuring Activity 2024
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	300		300
Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments					2,800	$ 2,800
Restructuring reserve	1,500		1,500
Facility Closing | Restructuring Activity 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			7,300
Restructuring reserve	$ 900		900
United States
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						5
United States | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring reserve related charges			500
United States | Employee Severance | Restructuring Activity 2021
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			$ 100
United States and Asia Pacific | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring reserve related charges					4,000
United States and Europe | Employee Severance | Restructuring Activity 2021
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments					$ 200
Boston
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						1
Philadelphia
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						1
Phoenix
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						1
San Francisco
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						2
Europe
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						3
The Netherlands
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						1
London, England
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						1
Paris, France
Restructuring Cost and Reserve [Line Items]
Number of leased office space exited | leasedOfficeSpace						1