DEBT - Long-term Debt, Net (Details) - USD ($) $ in Millions	Sep. 30, 2024	Mar. 31, 2024
Debt Instrument [Line Items]
Total	$ 3,076.0	$ 3,075.9
Unamortized discount and issuance costs	(20.1)	(17.6)
Long-term debt, net	3,055.9	3,058.3
Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 3,099.2	$ 2,999.6
2025 Notes
Debt Instrument [Line Items]
Annual Interest Rate	3.55%	3.55%
Total		$ 600.0
2025 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total		$ 588.9
2026 Notes
Debt Instrument [Line Items]
Annual Interest Rate	5.00%	5.00%
Total	$ 550.0	$ 550.0
2026 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 555.6	$ 547.6
2027 Notes
Debt Instrument [Line Items]
Annual Interest Rate	3.70%	3.70%
Total	$ 600.0	$ 600.0
2027 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 592.6	$ 576.5
2028 Notes
Debt Instrument [Line Items]
Annual Interest Rate	4.95%	4.95%
Total	$ 800.0	$ 800.0
2028 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 816.5	$ 797.8
2029 Notes
Debt Instrument [Line Items]
Annual Interest Rate	5.40%
Total	$ 300.0
2029 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 312.4
2032 Notes
Debt Instrument [Line Items]
Annual Interest Rate	4.00%	4.00%
Total	$ 500.0	$ 500.0
2032 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 480.0	$ 462.9
2034 Notes
Debt Instrument [Line Items]
Annual Interest Rate	5.60%
Total	$ 300.0
2034 Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 316.1
2026 Convertible Notes
Debt Instrument [Line Items]
Annual Interest Rate	0.00%	0.00%
Total	$ 26.0	$ 25.9
2026 Convertible Notes | Significant other observable inputs (level 2)
Debt Instrument [Line Items]
Total	$ 26.0	$ 25.9