Stockholders' Equity - Narrative (Details)	12 Months Ended
	Mar. 31, 2021 vote $ / shares shares	Mar. 31, 2020 $ / shares shares	Mar. 31, 2019 shares	Nov. 08, 2018 USD ($)	Apr. 03, 2017 shares
Equity, Class of Treasury Stock [Line Items]
Common stock, authorized (in shares)	750,000,000	750,000,000
Common stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	1,000,000	1,000,000
Preferred stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01
Number of votes per common share | vote	1
Stock repurchase program, shares authorized					2,000,000,000.0
Stock repurchase program, increase (decrease) in authorized shares | $				$ 2,000,000,000.0
Treasury Stock Transactions [Abstract]
Common stock in treasury, at cost (in shares)	2,458,027	2,148,708	1,788,658
Common Stock | Shares Repurchased From Employees Related To Stock Option Plans
Treasury Stock Transactions [Abstract]
Accepted common stock in lieu of cash in connection with exercise of stock options (in shares)	4,050	38,902	42,008
Accepted common stock in lieu of cash in connection with the tax withholdings associated with the vesting and release of common stock (in shares)	305,269	321,148	729,703