Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Mar. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 8,510	$ 10,078
Accumulated Amortization	4,364	4,347
Net Carrying Value	4,146	5,731
Discontinued Operations - Held for sale \| HHS Business
Finite-Lived Intangible Assets [Line Items]
Intangible assets, net	1,308
Software
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	4,006	4,048
Accumulated Amortization	2,819	2,614
Net Carrying Value	1,187	1,434
Customer related intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	4,246	5,795
Accumulated Amortization	1,502	1,697
Net Carrying Value	2,744	4,098
Other intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	258	235
Accumulated Amortization	43	36
Net Carrying Value	$ 215	$ 199

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

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