Segment Information - Narratives (Details)	12 Months Ended
Dec. 31, 2020 segment country	Dec. 31, 2019 country	Dec. 31, 2018 country
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	2
Non-US [Member] \| Revenue Benchmark [Member]
Segment Reporting Information [Line Items]
Number Of Countries Accounting For More Than Ten Percent of Non United States Revenue \| country	0	0	0
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Comcast [Member] \| Revenue Benchmark [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Comcast [Member] \| Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	20.00%	23.00%	15.00%

Number Of Countries Accounting For More Than Ten Percent of Non United States Revenue

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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-Name Accounting Standards Codification
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-Section 50
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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- Definition

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.

+ References

No definition available.

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