CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Adjustment	Common Stock and Additional Paid-in-Capital	Common Stock and Additional Paid-in-Capital Adjustment	Common Stock Held in Treasury	Accumulated Other Comprehensive Loss	Retained Earnings	Retained Earnings Adjustment
Balance, common stock shares issued (in shares) at Mar. 31, 2022			577,800,000
Beginning balance at Mar. 31, 2022	$ 5,894.8		$ 2,536.5		$ (796.3)	$ (20.6)	$ 4,175.2
Beginning balance (Accounting Standards Update 2020-06) at Mar. 31, 2022		$ (81.8)		$ (128.3)				$ 46.5
Beginning balance, common stock held in treasury (in shares) at Mar. 31, 2022					23,300,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	507.2						507.2
Other comprehensive income	4.0					4.0
Proceeds from sales of common stock through employee equity incentive plans (shares)			1,200,000
Proceeds from sales of common stock through employee equity incentive plans	13.4		$ 13.4
RSU withholdings (shares)			(300,000)
RSU withholdings	(19.4)		$ (19.4)
Treasury stock used for new issuances (shares)			(900,000)		(900,000)
Treasury stock used for new issuances	0.0		$ (16.5)		$ 16.5
Repurchase of common stock (in shares)					2,900,000
Repurchase of common stock	(195.2)				$ (195.2)
Settlement of convertible debt	(32.9)		(32.9)
Share-based compensation	40.8		$ 40.8
Cash dividend	(153.0)						(153.0)
Balance, common stock shares issued (in shares) at Jun. 30, 2022			577,800,000
Ending balance at Jun. 30, 2022	5,977.9		$ 2,393.6		$ (975.0)	(16.6)	4,575.9
Ending balance, common stock held in treasury (in shares) at Jun. 30, 2022					25,300,000
Balance, common stock shares issued (in shares) at Mar. 31, 2022			577,800,000
Beginning balance at Mar. 31, 2022	5,894.8		$ 2,536.5		$ (796.3)	(20.6)	4,175.2
Beginning balance (Accounting Standards Update 2020-06) at Mar. 31, 2022		$ (81.8)		$ (128.3)				$ 46.5
Beginning balance, common stock held in treasury (in shares) at Mar. 31, 2022					23,300,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,053.4
Other comprehensive income	9.0
Balance, common stock shares issued (in shares) at Sep. 30, 2022			577,800,000
Ending balance at Sep. 30, 2022	6,103.1		$ 2,356.1		$ (1,197.4)	(11.6)	4,956.0
Ending balance, common stock held in treasury (in shares) at Sep. 30, 2022					27,800,000
Balance, common stock shares issued (in shares) at Jun. 30, 2022			577,800,000
Beginning balance at Jun. 30, 2022	5,977.9		$ 2,393.6		$ (975.0)	(16.6)	4,575.9
Beginning balance, common stock held in treasury (in shares) at Jun. 30, 2022					25,300,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	546.2						546.2
Other comprehensive income	5.0					5.0
Proceeds from sales of common stock through employee equity incentive plans (shares)			1,400,000
Proceeds from sales of common stock through employee equity incentive plans	24.4		$ 24.4
RSU withholdings (shares)			(300,000)
RSU withholdings	(20.7)		$ (20.7)
Treasury stock used for new issuances (shares)			(1,100,000)		(1,100,000)
Treasury stock used for new issuances	0.0		$ (24.8)		$ 24.8
Repurchase of common stock (in shares)					3,600,000
Repurchase of common stock	(247.2)				$ (247.2)
Settlement of convertible debt	(58.2)		(58.2)
Share-based compensation	41.8		$ 41.8
Cash dividend	(166.1)						(166.1)
Balance, common stock shares issued (in shares) at Sep. 30, 2022			577,800,000
Ending balance at Sep. 30, 2022	$ 6,103.1		$ 2,356.1		$ (1,197.4)	(11.6)	4,956.0
Ending balance, common stock held in treasury (in shares) at Sep. 30, 2022					27,800,000
Balance, common stock shares issued (in shares) at Mar. 31, 2023	577,805,623		577,800,000
Beginning balance at Mar. 31, 2023	$ 6,513.6		$ 2,413.8		$ (1,660.2)	(4.1)	5,764.1
Beginning balance, common stock held in treasury (in shares) at Mar. 31, 2023	32,345,809				32,300,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 666.4						666.4
Other comprehensive income	(0.3)					(0.3)
Proceeds from sales of common stock through employee equity incentive plans (shares)			900,000
Proceeds from sales of common stock through employee equity incentive plans	15.3		$ 15.3
RSU withholdings (shares)			(300,000)
RSU withholdings	(15.7)		$ (15.7)
Treasury stock used for new issuances (shares)			(600,000)		(600,000)
Treasury stock used for new issuances	0.0		$ (14.7)		$ 14.7
Repurchase of common stock (in shares)					1,800,000
Repurchase of common stock	(141.2)				$ (141.2)
Settlement of convertible debt	(43.3)		(43.3)
Share-based compensation	45.4		$ 45.4
Cash dividend	(208.9)						(208.9)
Balance, common stock shares issued (in shares) at Jun. 30, 2023			577,800,000
Ending balance at Jun. 30, 2023	$ 6,831.3		$ 2,400.8		$ (1,786.7)	(4.4)	6,221.6
Ending balance, common stock held in treasury (in shares) at Jun. 30, 2023					33,500,000
Balance, common stock shares issued (in shares) at Mar. 31, 2023	577,805,623		577,800,000
Beginning balance at Mar. 31, 2023	$ 6,513.6		$ 2,413.8		$ (1,660.2)	(4.1)	5,764.1
Beginning balance, common stock held in treasury (in shares) at Mar. 31, 2023	32,345,809				32,300,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 1,333.0
Other comprehensive income	$ 1.3					1.3
Repurchase of common stock (in shares)	6,000,000
Repurchase of common stock	$ (483.5)
Balance, common stock shares issued (in shares) at Sep. 30, 2023	577,806,238		577,800,000
Ending balance at Sep. 30, 2023	$ 6,968.5		$ 2,415.1		$ (2,109.3)	(2.8)	6,665.5
Ending balance, common stock held in treasury (in shares) at Sep. 30, 2023	36,762,009				36,800,000
Balance, common stock shares issued (in shares) at Jun. 30, 2023			577,800,000
Beginning balance at Jun. 30, 2023	$ 6,831.3		$ 2,400.8		$ (1,786.7)	(4.4)	6,221.6
Beginning balance, common stock held in treasury (in shares) at Jun. 30, 2023					33,500,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	666.6						666.6
Other comprehensive income	1.6					1.6
Proceeds from sales of common stock through employee equity incentive plans (shares)			1,100,000
Proceeds from sales of common stock through employee equity incentive plans	25.3		$ 25.3
RSU withholdings (shares)			(200,000)
RSU withholdings	(14.7)		$ (14.7)
Treasury stock used for new issuances (shares)			(900,000)		(900,000)
Treasury stock used for new issuances	$ 0.0		$ (19.7)		$ 19.7
Repurchase of common stock (in shares)	4,200,000
Repurchase of common stock	$ (342.3)				(342.3)
Settlement of convertible debt	(22.0)		(22.0)
Share-based compensation	45.4		$ 45.4
Cash dividend	$ (222.7)						(222.7)
Balance, common stock shares issued (in shares) at Sep. 30, 2023	577,806,238		577,800,000
Ending balance at Sep. 30, 2023	$ 6,968.5		$ 2,415.1		$ (2,109.3)	$ (2.8)	$ 6,665.5
Ending balance, common stock held in treasury (in shares) at Sep. 30, 2023	36,762,009				36,800,000