Stockholders' Equity Stock Repurchase Program (Details) - 2016 Program [Member] $ in Millions	Oct. 31, 2017 USD ($)
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 500.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 250.3

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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