Commitment made to pay deferred cash remuneration expressed as a percentage of the individual's base salary.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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Pension and Other Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	May 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Net projected benefit obligations				$ 489
Net projected assets	$ 155	$ 247		419
Other assets				7
Other long-term liabilities				$ 77
Defined contribution plan expense	44	33	$ 15
Deferred compensation liability included in other long-term liabilities	$ 12	$ 13
Enterprise Services LLC Deferred Compensation Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible deferred cash compensation	100.00%
Management \| Enterprise Services LLC Deferred Compensation Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible deferred cash compensation	75.00%
Scenario 1
Defined Benefit Plan Disclosure [Line Items]
Employer percentage match	100.00%
Percentage of employee's annual pay	3.00%
Scenario 2
Defined Benefit Plan Disclosure [Line Items]
Employer percentage match	50.00%
Percentage of employee's annual pay	2.00%