Goodwill and Intangible Assets - (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($) segment	Mar. 31, 2020 USD ($)
Goodwill:
Number of operating segments | segment	1
Changes in goodwill
Beginning balance	$ 296,493	$ 279,543
Goodwill arising from acquisitions		27,316
Purchase price adjustment	(4,526)
Foreign currency translation adjustments	(224)	(10,366)
Ending balance	291,743	296,493
Acquisition costs and goodwill deductible for tax purposes	284,020
Acquisition costs and goodwill not deductible for tax purposes	20,627
Fiscal 2020 aquisitions
Changes in goodwill
Beginning balance	22,790
Purchase price adjustment	4,526
Ending balance		22,790
Acquired certain assets of a small consulting company purchase price
Cash paid at closing		9,651
Additional earn-out consideration		$ 9,853
Amount paid towards earn-out consideration	4,922
Probable and estimable value of the contingent consideration	$ 2,579