Stock Transactions Stock Transactions (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Jul. 31, 2015	Jan. 22, 2015
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 450.0	$ 150.0	$ 300.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 125.7

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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