Capital Leases - Narrative (Details) - USD ($) $ in Millions	5 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2019	Mar. 31, 2018	Oct. 31, 2016
Leases [Abstract]
Capital lease obligations		$ 305	$ 304
Increase in capital leases obligations		23
Increase to property and equipment		19
Increase to intangible assets		4
Interest expense on capital leases	$ 10	$ 20	$ 12	$ 31

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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-Publisher FASB
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-SubTopic 30
-Section 50
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The financing charge for leasing arrangements meeting the criteria for capitalization.

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Amount of fresh-start adjustment to current capital lease obligations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
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- Definition

The increase (decrease) during the reporting period in intangible assets (for example patents and licenses).

+ References

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Amount of increase (decrease) of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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