Significant Accounting Policies - Receivables, Net (Details) - USD ($) $ in Millions	Mar. 31, 2021	Mar. 31, 2020
Receivables, Net, Current [Abstract]
Customer accounts	$ 17,106	$ 17,201
Other	2,325	3,014
Total receivables	19,431	20,215
Allowances	(250)	(265)
Receivables, net	$ 19,181	$ 19,950

Accounts Receivable, Customer Accounts, Gross

No definition available.

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- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

+ References

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- Definition

Amount of allowance for credit loss on accounts receivable, classified as current.

+ References

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- Definition

Amount, before allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

+ References

No definition available.

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

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- References

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