Stockholders’ Equity - Additional Information (Details) - USD ($) $ in Millions	Jan. 31, 2018	Jul. 21, 2017
Stock Repurchase Program July 2016
Equity, Class of Treasury Stock [Line Items]
Authorized repurchase amount	$ 6,000	$ 3,000

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.

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