Summary of Components of Other Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Goodwill [Line Items]
Other investments	$ 38,741	$ 24,584	$ 12,649	$ 7,249
Operating lease right-of-use assets (Note 9)	11,760
Cross-currency swap (Note 4)	3,786
Other intangible assets and other assets	7,664	4,336
Total other assets	117,655	85,115
Shockwave Medical
Goodwill [Line Items]
Fair value of investment	$ 55,704	$ 56,195