Stockholders' Equity (Details Textual)	Jan. 31, 2018 USD ($)
Class A and Class B [Member] \| 2018 Authorization [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase authorization	$ 3,000,000,000.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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