Legal Proceedings (Narrative) (Detail) - USD ($) $ in Millions	Apr. 19, 2017	Oct. 27, 2017
Loss Contingencies [Line Items]
Litigation Settlement, Amount	$ 19.5
Insurance Settlements Receivable		$ 13.0

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.

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