Segment Information (Parentheticals) (Details 5) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Charter and Comcast
Revenue, Major Customer [Line Items]
Reduction to net sales in connection with warrants	$ 0	$ 0	$ 30,200

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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