Income Taxes - Income Tax (Benefit) Provision from Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Income before income taxes:
U.S.	$ 555.5	$ 674.7	$ 132.2
Foreign	1,810.4	2,235.0	1,350.3
Income before income taxes	2,365.9	2,909.7	1,482.5
Current provision (benefit):
U.S. Federal	347.5	389.5	191.6
State	20.0	5.0	3.7
Foreign	118.7	72.0	(6.2)
Total current provision	486.2	466.5	189.1
Deferred provision (benefit):
U.S. Federal	(106.4)	53.7	(78.7)
State	(12.3)	4.6	(9.1)
Foreign	91.5	147.2	95.7
Total deferred provision (benefit)	(27.2)	205.5	7.9
Income tax provision	459.0	672.0	197.0
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Computed expected income tax provision	496.8	611.0	311.3
State income taxes, net of federal benefit	15.7	8.6	3.5
Effects of foreign operations - rate differential	(149.3)	(184.0)	(96.8)
Effects of foreign operations - other, net of foreign tax credits	212.2	258.9	139.9
Foreign-derived intangible income ("FDII")	(3.6)	0.0	(27.3)
Change in uncertain tax positions	5.8	50.6	(47.1)
Share-based compensation	(8.4)	(11.4)	(17.6)
R&D tax credits	(69.8)	(63.8)	(49.5)
Income tax holidays	(22.5)	(26.7)	(22.5)
Convertible debt settlement	0.7	0.7	(25.5)
Other	10.0	19.0	28.6
Change in valuation allowance	(28.6)	9.1	0.0
Income tax provision	$ 459.0	$ 672.0	$ 197.0