Subsequent Events - Red Hat Acquisition (Details) - USD ($) $ / shares in Units, $ in Millions		9 Months Ended
Oct. 28, 2018	Sep. 30, 2018
Subsequent Events
Estimated transaction value		$ 49
Subsequent Events \| Bridge Loan Credit Facility \| Expected
Subsequent Events
Term of debt instrument	364 days
Credit facility committed amount	$ 20,000
Subsequent Events \| Red Hat, Inc. \| Expected
Subsequent Events
Cash to be paid to acquiree shareholders (in dollars per share)	$ 190
Estimated transaction value	$ 34,000

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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