Income Taxes (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Apr. 01, 2017
Income Tax Disclosure [Abstract]
Domestic entities		$ (2,928)	$ 511	$ 454
Entities outside the United States		(2,300)	1,004	850
(Loss) income from continuing operations, before taxes		(5,228)	1,515	1,304
Income Tax Contingency [Line Items]
Transition tax included in current provision (benefit)		(31)	(44)	332
Interest and penalties for uncertain tax positions included in current provision (benefit)		2	1	2
Income tax holiday		$ 0	$ 2	$ 5
Income tax holiday (in dollars per share)		$ 0.0	$ 0.01	$ 0.02
Change in foreign earnings to be repatriated	$ (492)
Hewlett Packard Enterprise Services
Income Tax Contingency [Line Items]
Accrued income taxes					$ 8
Tax indemnification receivable related to net uncertain tax positions					44
Tax indemnification receivable related to other tax payables					87
Tax indemnification payable related to other tax receivables					$ 123
Discontinued Operations | USPS Separation
Income Tax Contingency [Line Items]
Tax indemnification receivable related to disposal			$ 72
Tax indemnification payable related to disposal			$ 45