Legal and Regulatory Proceedings Legal and Regulatory Proceedings (Details) $ in Millions	9 Months Ended
Sep. 30, 2017 USD ($)
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party	$ 20.0

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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