Stock Incentive Plans - Schedule of Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Total share-based compensation cost	$ 26	$ 6	$ 77	$ 42
Related income tax benefit	4	2	11	7
Total intrinsic value of options exercised	0	0	6	0
Tax benefits from exercised stock options and awards	$ 0	$ 1	$ 15	$ 5

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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