Segment Reporting and Significant Concentration - Summary of Revenue from Significant Customers (Details) - Customer Concentration Risk - Sales Revenue, Net	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Comcast
Segment Reporting Information [Line Items]
Revenue by Major Client, Percentage	22.00%	23.00%	25.00%
Charter
Segment Reporting Information [Line Items]
Revenue by Major Client, Percentage	21.00%	20.00%	20.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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