Share-Based Compensation - Equity Incentive Plans, RSU and PSU Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Weighted Average Grant Date Fair Value
Share price (in dollars per share)	$ 75.14
Unvested share-based payment awards	$ 303.8
Restricted stock units' weighted average remaining expense recognition period (in years)	1 year 11 months 1 day
Restricted Stock Units and Performance Stock Units
Number of Shares
Nonvested shares at beginning of period (in shares)	11,883,818	11,484,106	12,583,924
Granted (in shares)	2,995,991	4,678,494	4,364,088
Forfeited (in shares)	(978,325)	(514,110)	(681,318)
Vested (in shares)	(3,795,469)	(3,764,672)	(4,782,588)
Nonvested shares at end of period (in shares)	10,106,015	11,883,818	11,484,106
Weighted Average Grant Date Fair Value
Nonvested shares at beginning of period (in dollars per share)	$ 44.77	$ 38.06	$ 32.41
Granted (in dollars per share)	74.36	50.69	44.09
Forfeited (in dollars per share)	51.17	41.69	37.75
Vested (in dollars per share)	43.77	32.07	28.74
Nonvested shares at end of period (in dollars per share)	$ 53.30	$ 44.77	$ 38.06
RSU Vested aggregate intrinsic value	$ 287.6	$ 218.5	$ 223.9
Total intrinsic value of RSU's outstanding	$ 759.4
Performance Shares
Number of Shares
Granted (in shares)	145,188	140,160	32,734

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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