Held for Sale - Narrative (Details) - USD ($) $ in Millions	4 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2020	Mar. 31, 2019
Discontinued Operations Disclosures
Assets held for sale	$ 906	$ 906	$ 0
Liabilities held for sale	683	683	$ 0
Held-for-sale
Discontinued Operations Disclosures
Assets held for sale	906	906
Liabilities held for sale	683	683
German Wholesale Business \| Held-for-sale
Discontinued Operations Disclosures
Assets held for sale	842	842
Liabilities held for sale	656	656
After-tax impairment charge		$ 275
Cumulative foreign currency translation adjustment	$ 3

Disposal Group, Not Discontinued Operation, Loss (Gain) on Write-down, Net of Tax

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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- Definition

Amount of foreign currency translation gain (loss) in the disposal group, including discontinued operation, recognized in the statement of income as a result of the sale or complete or substantially complete liquidation of an investment in a foreign entity.

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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.

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