Contingencies - Additional Information (Detail) - USD ($) $ in Thousands			6 Months Ended		12 Months Ended
	May 08, 2023	Jul. 08, 2022	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Loss Contingencies [Line Items]
Revenues					$ 4,283,758	$ 2,556,158	$ 2,417,179
Interest income					96,258	19,512	504
Product [Member]
Loss Contingencies [Line Items]
Revenues					1,279,164	954,126	$ 860,726
Positive Outcome of Litigation [Member]
Loss Contingencies [Line Items]
Legal settlement received	$ 97,500	$ 62,200
Revenues			$ 99,900	$ 55,800
Interest income			$ 7,200	$ 6,400
Unfavorable Regulatory Action [Member]
Loss Contingencies [Line Items]
U.S. government contract-related reserves					$ 16,600	$ 12,900