Other Assets - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2020
Goodwill [Line Items]
Shares held by the company		0.3		0.3
Intangible asset, amortized useful life	15 years
License Manufacturing Rghts to Technology
Goodwill [Line Items]
Payments to third party				$ 3,600
Other Intangible Assets
Goodwill [Line Items]
Intangible asset, amortized useful life				15 years
Other Income (Expense)
Goodwill [Line Items]
Impairment loss in other investment		$ 0		$ 800
Shockwave Medical
Goodwill [Line Items]
Fair value of investment		30,779		30,779		$ 55,704
Shockwave Medical | Other Income (Expense)
Goodwill [Line Items]
Unrealized gain (loss) recorded in other income		6,200	$ 17,800	32,300	$ 13,300
Medical Device Companies [Member]
Goodwill [Line Items]
Additional investments		$ 23,000		$ 26,100