Capital Leases - Schedule of Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Dec. 31, 2018	Mar. 31, 2018
Leases [Abstract]
Remainder of fiscal year 2019	$ 51
2020	127
2021	79
2022	47
2023	12
Thereafter	1
Total minimum lease payments	317
Less: Amount representing interest and executory costs	28
Present value of net minimum lease payments	289
Less: Current capital lease liability	140	$ 160
Non-current capital lease liability	$ 149	$ 144

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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-Topic 210
-SubTopic 10
-Section S99
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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount of minimum lease payments for capital leases due in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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