Debt - Schedule of Debt (Details) - USD ($) $ in Millions	6 Months Ended
Sep. 30, 2018	Mar. 31, 2018
Debt Instrument [Line Items]
Total debt	$ 2,516
Less: current maturities of long-term debt, net (1)	(80)	$ 0
Less: unamortized debt issuance costs and premiums	(21)
Total long-term debt, net of current maturities	2,415	$ 0
Secured debt
Debt Instrument [Line Items]
Total debt	2,450
Debt issuance costs	7
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	1.75%
Secured debt \| Term Loan A Facilities (Tranche 1)
Debt Instrument [Line Items]
Total debt	$ 322
Secured debt \| Term Loan A Facilities (Tranche 1) \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.625%
Secured debt \| Term Loan A Facilities (Tranche 2)
Debt Instrument [Line Items]
Total debt	$ 1,629
Secured debt \| Term Loan A Facilities (Tranche 2) \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Secured debt \| Term Loan B Facility
Debt Instrument [Line Items]
Total debt	$ 499
Secured debt \| Term Loan B Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Unsecured debt
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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- Definition

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

No definition available.

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

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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

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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- Definition

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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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