Debt - Schedule of Debt (Details) - USD ($) $ in Millions	9 Months Ended
Dec. 31, 2018	Mar. 31, 2018
Debt Instrument [Line Items]
Total debt	$ 2,484
Less: current maturities of long-term debt, net	(79)	$ 0
Less: unamortized debt issuance costs and premiums	(21)
Total long-term debt, net of current maturities	2,384	$ 0
Secured Debt
Debt Instrument [Line Items]
Total debt	2,418
Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	$ 0
Secured Debt \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Secured Debt \| Term Loan A Facilities (Tranche 1)
Debt Instrument [Line Items]
Total debt	$ 312
Secured Debt \| Term Loan A Facilities (Tranche 1) \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.375%
Secured Debt \| Term Loan A Facilities (Tranche 2)
Debt Instrument [Line Items]
Total debt	$ 1,608
Secured Debt \| Term Loan A Facilities (Tranche 2) \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Secured Debt \| Term Loan B Facility
Debt Instrument [Line Items]
Total debt	$ 498
Secured Debt \| Term Loan B Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Secured Debt \| Term Loan A and B Facilities
Debt Instrument [Line Items]
Debt issuance costs	$ 8
Senior unsecured EDS Notes
Debt Instrument [Line Items]
Total debt	$ 66
Stated interest rate	7.45%
Unamortized premiums	$ 12

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

+ References

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after accumulated amortization, of debt premium.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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