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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Concentration Risk [Line Items]
Revenue recognized that was included within the deferred revenue balance	$ 40,400,000	$ 54,100,000
Amortization of capitalized contract costs	2,100,000	2,300,000	$ 2,200,000
Capitalized software impairment	1,800,000
Leasehold improvement impairment charge	4,300,000
Impairment charges of property and equipment		0	0
Impairment of goodwill	0	0	0
Foreign currency remeasurement gain (loss)	(315,000)	(1,453,000)	2,685,000
Advertising expense	$ 300,000	$ 500,000	$ 700,000
Accounts Receivable \| Customer Concentration Risk \| Two Customers
Concentration Risk [Line Items]
Concentration risk	10.00%	10.00%
Net Revenue \| Customer Concentration Risk \| Comcast
Concentration Risk [Line Items]
Concentration risk	44.00%	44.00%	39.00%
Net Revenue \| Customer Concentration Risk \| Charter Communications
Concentration Risk [Line Items]
Concentration risk		18.00%
TVN
Concentration Risk [Line Items]
Research and development tax credits receivables from French government	$ 5,900,000	$ 6,200,000	$ 5,400,000
Foreign Exchange Forward
Concentration Risk [Line Items]
Derivative, term of contract (in months)	3 months
Other Expense
Concentration Risk [Line Items]
Foreign currency remeasurement gain (loss)	$ 2,400,000	$ (200,000)	$ (300,000)
Minimum
Concentration Risk [Line Items]
Lessee, operating lease, term of contract (in years)	1 year
Minimum \| Net Revenue \| Customer Concentration Risk \| Comcast
Concentration Risk [Line Items]
Concentration risk	10.00%
Minimum \| Net Revenue \| Customer Concentration Risk \| Charter Communications
Concentration Risk [Line Items]
Concentration risk	10.00%
Maximum
Concentration Risk [Line Items]
Lessee, operating lease, term of contract (in years)	8 years
Furniture and fixtures
Concentration Risk [Line Items]
Property, plant and equipment estimated useful life (in years)	5 years
Software
Concentration Risk [Line Items]
Property, plant and equipment estimated useful life (in years)	3 years
Machinery and equipment
Concentration Risk [Line Items]
Property, plant and equipment estimated useful life (in years)	4 years