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v3.19.3.a.u2

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands |  |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2019 USD ($) | Jan. 01, 2017 USD ($) | Mar. 29, 2019 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) Customer ReportingUnit segment | Dec. 31, 2018 USD ($) Customer | Dec. 31, 2017 USD ($) | Sep. 27, 2019 USD ($) | Dec. 31, 2015 USD ($)
Cash and cash equivalents maximum maturity |  |  |  |  |  |  | 3 months |  |  |  |
Investments in Equity Securities |  |  |  |  |  |  | $ 3,593 | $ 3,593 |  |  |
Cash and cash equivalents |  |  |  |  |  |  | 93,058 | 65,989 | $ 57,024 |  |
Accounts receivable, net |  |  |  |  |  |  | 88,500 | 81,795 |  |  |
Debts with French government agencies & other |  |  |  |  |  |  | 17,224 | 19,859 |  |  |
Capitalized Software Development Costs for Software Sold to Customers |  |  |  |  |  |  | 1,100 | 900 | 1,100 |  |
Hosting Arrangement, Service Contract, Implementation Cost, Capitalized, before Accumulated Amortization |  |  |  |  |  |  | 3,600 |  |  |  |
Goodwill |  |  |  |  |  |  | $ 239,780 | 240,618 | 242,827 |  |
Number of reporting units | ReportingUnit |  |  |  |  |  |  | 2 |  |  |  |
Goodwill, Impairment Loss |  |  |  |  |  |  | $ 0 | 0 | 0 |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  |  |  | 0 | 0 | 0 |  |
Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net |  |  |  |  |  |  | 0 | 0 |  |  |
Advertising expense |  |  |  |  |  |  | $ 700 | $ 1,000 | 700 |  |
Net Accumulated Gain or Loss as a Percentage of Projected Plan Benefit Obligation |  |  |  |  |  |  | 10.00% |  |  |  |
More Likely Than Not Threshold Recognition of Uncertain Tax Position |  |  |  |  |  |  | 50.00% |  |  |  |
Number of reportable segments | segment |  |  |  |  |  |  | 2 |  |  |  |
Operating lease right-of-use assets |  |  |  |  |  |  | $ 27,491 |  |  |  |
Operating Lease, Liability |  |  |  |  |  |  | 35,214 |  |  |  |
Operating Lease, Payments |  |  |  |  |  |  | $ 9,702 |  |  |  |
Furniture and Fixtures [Member] |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment estimated useful life |  |  |  |  |  |  | 5 years |  |  |  |
Internal Use Software [Member] |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment estimated useful life |  |  |  |  |  |  | 3 years |  |  |  |
Machinery and Equipment [Member] |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment estimated useful life |  |  |  |  |  |  | 4 years |  |  |  |
Leasehold Improvements [Member] |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment leasehold improvements useful lives |  |  |  |  |  |  | shorter of the remaining useful lives of the assets or the lease term of the respective assets |  |  |  |
Leaseholds and Leasehold Improvements [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Lessee, Operating Lease, Term of Contract |  |  |  |  |  |  | 1 year |  |  |  |
Leaseholds and Leasehold Improvements [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Lessee, Operating Lease, Term of Contract |  |  |  |  |  |  | 11 years |  |  |  |
Foreign Exchange Forward [Member] | Not Designated as Hedging Instrument, Trading [Member] |  |  |  |  |  |  |  |  |  |  |
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net |  |  |  |  |  |  | $ 0 |  |  |  |
Forward Contracts [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative, Term of Contract |  |  |  |  |  |  | 12 months |  |  |  |
Software [Member] |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment estimated useful life |  |  |  |  |  |  | 3 years |  |  |  |
Accounts Receivable [Member] |  |  |  |  |  |  |  |  |  |  |
Entity-wide revenue, major customer, revenue or accounts receivable percentage |  |  |  |  |  |  | 10.00% | 10.00% |  |  |
TVN [Member] |  |  |  |  |  |  |  |  |  |  |
Research and Development Tax Credits Receivables from French Government |  |  |  |  |  |  | $ 4,700 | $ 5,900 | 5,900 |  |
Other Expense [Member] |  |  |  |  |  |  |  |  |  |  |
Remeasurement Losses, Reporting Currency Denominated, Value |  |  |  |  |  |  | 1,500 | $ 600 | $ 2,200 |  |
Accounting Standards Update 2016-09 [Member] |  |  |  |  |  |  |  |  |  |  |
Cumulative Effect on Retained Earnings, Net of Tax | [1] | $ 1,400 |  |  |  |  |  |  |  |  |
Accounting Standards Update 2016-02 [Member] |  |  |  |  |  |  |  |  |  |  |
Operating lease right-of-use assets |  | 23,300 |  |  |  |  |  |  |  |  |
Operating Lease, Liability |  | 23,300 |  |  |  |  |  |  |  |  |
Operating Lease, Payments |  | 0 |  |  |  |  |  |  |  |  |
Accounting Standards Update 2018-07 [Member] |  |  |  |  |  |  |  |  |  |  |
Cumulative Effect on Retained Earnings, Net of Tax | [1] |  |  |  | $ 1,400 |  |  |  |  |  |
JPMORGAN CHASE BANK N.A. [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Current Borrowing Capacity |  |  |  |  |  |  | $ 0 |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  | 1.25% |  |  |  |
JPMORGAN CHASE BANK N.A. [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Current Borrowing Capacity |  |  |  |  |  |  | $ 25,000 |  |  |  |
Cash Flow Hedging [Member] | Forward Contracts [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative, Term of Contract |  |  |  |  |  |  | 12 months |  |  |  |
Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member] |  |  |  |  |  |  |  |  |  |  |
Cumulative Effect on Retained Earnings, Net of Tax |  | 1,400 | [1] | $ (69) |  |  |  |  |  |  |
Retained Earnings [Member] | Accounting Standards Update 2016-02 [Member] |  |  |  |  |  |  |  |  |  |  |
Cumulative Effect on Retained Earnings, Net of Tax |  | $ 0 |  |  |  |  |  |  |  |  |
Additional Paid-in Capital [Member] | Accounting Standards Update 2016-09 [Member] |  |  |  |  |  |  |  |  |  |  |
Cumulative Effect on Retained Earnings, Net of Tax |  |  |  | $ 69 |  |  |  |  |  |  |
Forecast [Member] |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Actuarial Gain (Loss), Immediate Recognition as Component in Net Periodic Benefit (Cost) Credit |  |  |  |  |  | $ 0 |  |  |  |  |
Credit Concentration Risk [Member] | Accounts Receivable [Member] |  |  |  |  |  |  |  |  |  |  |
Number of significant customers for accounts receivable | Customer |  |  |  |  |  |  | 1 | 2 |  |  |
Convertible Note due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  | $ 115,500 |  |  | $ 115,500 |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  | 2.00% |  |  | 2.00% |
Convertible Note due 2020 [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  | $ 45,785 | $ 128,250 |  |  | $ 128,250
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  | 4.00% |  |  |  | 4.00%
Comcast [Member] | Net Revenue [Member] |  |  |  |  |  |  |  |  |  |  |
Entity-wide revenue, major customer, revenue or accounts receivable percentage |  |  |  |  |  |  | 10.00% | 10.00% |  |  |
Comcast [Member] | Customer Concentration Risk [Member] | Net Revenue [Member] |  |  |  |  |  |  |  |  |  |  |
Number Of Customers Accounting For More Than Ten Percent of Revenue | Customer |  |  |  |  |  |  | 1 | 1 |  |  |
Entity-wide revenue, major customer, revenue or accounts receivable percentage |  |  |  |  |  |  | 23.00% | 15.00% |  |  |
[1] | See Note 2, “Summary of Significant Accounting Policies-Recently Adopted Accounting Pronouncements,” for more information on the adoption of ASC 718, Compensation-Stock Compensation (“Topic 718”) issued by the Financial Accounting Standards Board.

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