Acquisitions - Luxoft, Purchase Price Allocation (Details) - USD ($) $ in Millions	Mar. 31, 2021	Mar. 31, 2020	Jun. 14, 2019	Mar. 31, 2019
Business Acquisition [Line Items]
Goodwill	$ 641	$ 2,017		$ 7,606
Luxoft
Business Acquisition [Line Items]
Cash and cash equivalents			$ 113
Accounts receivable			233
Other current assets			15
Total current assets			361
Property and equipment			31
Intangible assets			577
Other assets			99
Total assets acquired			1,068
Accounts payable, accrued payroll, accrued expenses, and other current liabilities			(121)
Deferred revenue			(8)
Long-term deferred tax liabilities and income tax payable			(106)
Other liabilities			(72)
Total liabilities assumed			(307)
Net identifiable assets acquired			761
Goodwill			1,262
Total consideration transferred			$ 2,023