Receivables - Reconciliation of DPP (Details) - DE Purchasers $ in Millions	6 Months Ended
Sep. 30, 2020 USD ($)
Transfer of Financial Assets Accounted for as Sales, Deferred Purchase Price [Roll Forward]
Beginning balance	$ 103
Transfers of receivables	417
Collections	(420)
Change in funding availability	2
Facility amendments	(102)
Ending balance	$ 0

Transfer Of Financial Assets Accounted For As Sales, Deferred Purchase Price Receivable

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Transfer Of Financial Assets Accounted For As Sales, Deferred Purchase Price Receivable, Collections

No definition available.

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Transfer Of Financial Assets Accounted For As Sales, Deferred Purchase Price Receivable, Facility Amendments

No definition available.

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Transfer Of Financial Assets Accounted For As Sales, Deferred Purchase Price Receivable, Increase (Decrease) In Funding Availability

No definition available.

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Transfer Of Financial Assets Accounted For As Sales, Deferred Purchase Price Receivable, Transfer of Receivables

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Transfer of Financial Assets Accounted for as Sales, Deferred Purchase Price [Roll Forward]

No definition available.

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