Major Classes of Assets and Liabilities Allocated Purchase Price (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Oct. 25, 2018	Jun. 30, 2018
Business Acquisition [Line Items]
Goodwill	$ 41,577		$ 35,683
GitHub Inc
Business Acquisition [Line Items]
Cash, cash equivalents, and short-term investments		$ 234
Goodwill	5,400	5,441
Intangible assets	$ 1,300	1,298
Other assets		157
Other liabilities		(206)
Total		$ 6,924