Equity Narrative (Details) $ in Millions	Aug. 03, 2017 USD ($)
Common Class C, Non-Voting [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 5.4

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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