Casa Systems (CASSQ) 10-K 25 Feb 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Jan. 31, 2022	Jun. 30, 2021
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Registrant Name	Casa Systems, Inc.
Entity Central Index Key	0001333835
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
ICFR Auditor Attestation Flag	false
Entity Public Float			$ 280.7
Entity Common Stock, Shares Outstanding		84,446,788
Entity File Number	001-38324
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	75-3108867
Entity Address, Address Line One	100 Old River Road
Entity Address, City or Town	Andover
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01810
City Area Code	978
Local Phone Number	688-6706
Document Annual Report	true
Document Transition Report	false
Title of 12(b) Security	Common Stock, $0.001 par value per share
Trading Symbol	CASA
Security Exchange Name	NASDAQ
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	Boston, Massachusetts
Documents Incorporated by Reference	Portions of the Registrant’s definitive proxy statement relating to its 2022 Annual Stockholders’ Meeting expected to be filed pursuant to Regulation 14A within 120 days after the Registrant’s fiscal year end of December 31, 2021 are incorporated by reference into Part III of this Annual Report on Form 10-K.
Auditor One
Document Information [Line Items]
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	238
Auditor Location	Boston, Massachusetts

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 154,703	$ 157,455
Accounts receivable, net of provision for doubtful accounts of $117 and $58 as of December 31, 2021 and 2020, respectively	85,774	94,124
Inventory	84,828	101,204
Prepaid expenses and other current assets	5,746	3,864
Prepaid income taxes	23,963	14,087
Total current assets	355,014	370,734
Property and equipment, net	23,508	28,880
Accounts receivable, net of current portion	115	143
Deferred tax assets	101	1,150
Goodwill	50,177	50,177
Intangible assets, net	31,144	35,844
Other assets	8,648	6,038
Total assets	468,707	492,966
Current liabilities:
Accounts payable	28,087	41,203
Accrued expenses and other current liabilities	41,382	39,793
Accrued income taxes	4,991	7,463
Deferred revenue	14,473	15,531
Current portion of long-term debt, net of unamortized debt issuance costs	1,924	15,171
Total current liabilities	90,857	119,161
Accrued income taxes, net of current portion	7,732	9,520
Deferred tax liabilities	5,293	7,282
Deferred revenue, net of current portion	7,012	3,520
Long-term debt, net of current portion and unamortized debt issuance costs	274,193	276,085
Other non-current liabilities	1,701	1,024
Total liabilities	386,788	416,592
Commitments and contingencies (Note 18)
Stockholders’ equity:
Preferred stock, $0.001 par value; 5,000 shares authorized; no shares issued and outstanding
Common stock, $0.001 par value; 500,000 shares authorized; 87,815 and 85,329 shares issued as of December 31, 2021 and 2020, respectively; 84,422 and 83,607 shares outstanding as of December 31, 2021 and 2020, respectively	88	85
Treasury stock, at cost; 3,393 and 1,722 shares at December 31, 2021 and 2020, respectively	(13,645)	(4,826)
Additional paid-in capital	193,654	183,041
Accumulated other comprehensive income (loss)	878	337
Accumulated deficit	(99,056)	(102,263)
Total stockholders’ equity	81,919	76,374
Total liabilities and stockholders’ equity	$ 468,707	$ 492,966

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Provision for doubtful accounts	$ 117	$ 58
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares, outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	87,815,000	85,329,000
Common stock, shares outstanding	84,422,000	83,607,000
Treasury stock, shares	3,393,000	1,722,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 401,325	$ 393,246	$ 282,297
Cost of revenue:
Total cost of revenue	213,145	192,647	119,765
Gross profit	188,180	200,599	162,532
Operating expenses:
Research and development	84,362	84,370	83,331
Selling, general and administrative	85,563	92,016	88,320
Total operating expenses	169,925	176,386	171,651
Income (loss) from operations	18,255	24,213	(9,119)
Other income (expense):
Interest income	362	999	4,406
Interest expense	(14,958)	(16,895)	(20,522)
(Loss) gain on foreign currency, net	(2,113)	452	298
Other income, net	1,948	980	522
Total other income (expense), net	(14,761)	(14,464)	(15,296)
Income (loss) before provision for (benefit from) income taxes	3,494	9,749	(24,415)
Provision for (benefit from) income taxes	287	(15,052)	23,791
Net income (loss)	3,207	24,801	(48,206)
Other comprehensive income (loss)—foreign currency translation adjustment, net of tax	541	2,559	(1,064)
Comprehensive income (loss)	3,748	27,360	(49,270)
Net income (loss) attributable to common stockholders:
Basic and diluted	$ 3,207	$ 24,801	$ (48,206)
Net income (loss) per share attributable to common stockholders:
Basic	$ 0.04	$ 0.30	$ (0.57)
Diluted	$ 0.04	$ 0.29	$ (0.57)
Weighted-average number of shares used to compute net income (loss) per share attributable to common stockholders:
Basic	85,253	83,465	83,853
Diluted	88,857	85,278	83,853
Product
Revenue:
Total revenue	$ 353,942	$ 346,083	$ 241,377
Cost of revenue:
Total cost of revenue	208,451	187,706	113,059
Service
Revenue:
Total revenue	47,383	47,163	40,920
Cost of revenue:
Total cost of revenue	$ 4,694	$ 4,941	$ 6,706

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Accumulated DeficitCumulative Effect, Period of Adoption, Adjustment
Balance at Dec. 31, 2018	$ 74,856	$ 2,150	$ 83		$ 156,939	$ (1,158)	$ (81,008)	$ 2,150
Balance, shares at Dec. 31, 2018			82,961
Exercise of stock options and common stock issued upon vesting of equity awards, net of shares withheld for employee taxes	1,679		$ 1		1,678
Exercise of stock options and common stock issued upon vesting of equity awards, net of shares withheld for employee taxes, shares			1,372
Foreign currency translation adjustment, net of tax	(1,064)					(1,064)
Repurchases of treasury shares	(1,795)			$ (1,795)
Repurchases of treasury shares, shares				495
Stock-based compensation	10,944				10,944
Net income (loss)	(48,206)						(48,206)
Balance at Dec. 31, 2019	38,564		$ 84		169,561	(2,222)	(127,064)
Balance, shares at Dec. 31, 2019			84,333
Balance Treasury, shares at Dec. 31, 2019				495
Balance Treasury at Dec. 31, 2019				$ (1,795)
Exercise of stock options and common stock issued upon vesting of equity awards, net of shares withheld for employee taxes	555		$ 1		554
Exercise of stock options and common stock issued upon vesting of equity awards, net of shares withheld for employee taxes, shares			996
Foreign currency translation adjustment, net of tax	2,559					2,559
Repurchases of treasury shares	(3,031)			$ (3,031)
Repurchases of treasury shares, shares				1,227
Stock-based compensation	12,926				12,926
Net income (loss)	24,801						24,801
Balance at Dec. 31, 2020	$ 76,374		$ 85		183,041	337	(102,263)
Balance, shares at Dec. 31, 2020			85,329
Balance Treasury, shares at Dec. 31, 2020	1,722			1,722
Balance Treasury at Dec. 31, 2020	$ 4,826			$ (4,826)
Exercise of stock options and common stock issued upon vesting of equity awards, net of shares withheld for employee taxes	(4,203)		$ 3		(4,206)
Exercise of stock options and common stock issued upon vesting of equity awards, net of shares withheld for employee taxes, shares			2,486
Foreign currency translation adjustment, net of tax	541					541
Repurchases of treasury shares	(8,819)			$ (8,819)
Repurchases of treasury shares, shares				1,671
Stock-based compensation	14,819				14,819
Net income (loss)	3,207						3,207
Balance at Dec. 31, 2021	$ 81,919		$ 88		$ 193,654	$ 878	$ (99,056)
Balance, shares at Dec. 31, 2021			87,815
Balance Treasury, shares at Dec. 31, 2021	3,393			3,393
Balance Treasury at Dec. 31, 2021	$ 13,645			$ (13,645)

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement Of Stockholders Equity [Abstract]
Foreign currency translation adjustment, tax	$ 261	$ (49)	$ (57)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019
Operating activities:
Net income (loss)		$ 3,207		$ 24,801		$ (48,206)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization		15,680		17,970		14,722
Stock-based compensation		14,819		13,155		9,821
Deferred income taxes		(931)		(2,526)		19,641
Change in provision for excess and obsolete inventory		2,070		1,616		545
Increase (decrease) in provision for doubtful accounts		59		38		560
Gain on disposal of assets		37		115
Changes in operating assets and liabilities:
Accounts receivable		8,186		(350)		1,881
Inventory		14,101		(9,774)		(21,276)
Prepaid expenses and other assets		(2,017)		2,837		(3,679)
Prepaid income taxes		(9,884)		(11,745)		16
Accounts payable		(12,046)		17,015		1,554
Accrued expenses and other current liabilities		2,148		6,254		(7,827)
Accrued income taxes		(4,240)		5,297		2,724
Deferred revenue		2,409		(11,061)		(9,498)
Net cash provided by (used in) operating activities		33,598		53,642		(39,022)
Investing activities:
Purchases of property and equipment		(3,887)		(5,153)		(8,591)
Purchases of software licenses		(1,439)		(432)
Acquisition of a business, net of cash acquired						(109,431)
Net cash used in investing activities		(5,326)		(5,585)		(118,022)
Financing activities:
Principal repayments of debt		(16,275)		(9,644)		(6,820)
Borrowings on revolving credit facility				6,500
Proceeds from exercise of stock options		2,262		1,195		2,687
Payments of dividends and equitable adjustments		(98)		(683)		(2,590)
Repurchases of common stock		(8,819)		(3,031)		(1,795)
Employee taxes paid related to net share settlement of equity awards		(6,465)		(640)		(1,009)
Net cash used in financing activities		(29,395)		(6,303)		(9,527)
Effect of exchange rate changes on cash and cash equivalents		466		2,050		(378)
Net (decrease) increase in cash, cash equivalents and restricted cash		(657)		43,804		(166,949)
Cash, cash equivalents and restricted cash at beginning of year		158,461	[1]	114,657	[1]	281,606
Cash, cash equivalents and restricted cash at end of year	[1]	157,804		158,461		114,657
Supplemental disclosures of cash flow information:
Cash paid for interest		16,944		12,917		18,885
Cash paid for income taxes		10,194		2,969		4,334
Supplemental disclosures of non-cash investing and financing activities:
Purchases of property and equipment included in accounts payable		$ 200		128		727
Unpaid dividends and equitable adjustments included in accrued expenses and other current liabilities				63		731
Release of customer incentives included in accounts receivable and accrued expenses and other current liabilities				$ 157		$ 5,735
[1]	See Note 2 of the accompanying notes for a reconciliation of the ending balance of cash, cash equivalents and restricted cash shown in these consolidated statements of cash flows.

Nature of Business and Basis of

Nature of Business and Basis of Presentation	12 Months Ended
	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	1. Nature of Business and Basis of Presentation Casa Systems, Inc. (the “Company”) was incorporated under the laws of the State of Delaware on February 28, 2003. The Company is a global communications technology company headquartered in Andover, Massachusetts and has wholly owned subsidiaries in China, France, Canada, Ireland, Spain, Colombia, the Netherlands, Hong Kong, Australia, Germany, the United Kingdom and New Zealand. The Company offers physical, virtual and cloud-native 5G broadband and customer premise networking equipment for public and private high-speed data and multi-service communications networks. The Company’s core and edge broadband technology enables communications service providers and enterprises to cost-effectively and dynamically increase data network speed, add bandwidth capacity and new services, reduce network complexity and reduce operating and capital expenditures. The Company is subject to a number of risks similar to other companies of comparable size and other companies selling and providing services to the communications service provider (“CSP”) industry. These risks include, but are not limited to, the level of capital spending by CSPs, a lengthy sales cycle, dependence on the development of new products and services, unfavorable economic and market conditions, competition from larger and more established companies, limited management resources, dependence on a limited number of contract manufacturers and suppliers, the rapidly changing nature of the technology used by CSPs and reliance on resellers and sales agents. Failure by the Company to anticipate or to respond adequately to technological developments in its industry, changes in customer or supplier requirements, changes in regulatory requirements or industry standards, or any significant delays in the development or introduction of products could have a material adverse effect on the Company’s operating results, financial condition and cash flows. The Company is an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and may remain an emerging growth company until the last day of the fiscal year following the fifth anniversary of the Company’s initial public offering, subject to specified conditions. The JOBS Act provides that an emerging growth company can take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. The Company has elected not to “opt out” of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, the Company is required to adopt the new or revised standard at or prior to the time private companies are required to adopt the new or revised standard, provided that the Company continues to be an emerging growth company. The JOBS Act provides that the decision to take advantage of the extended transition period for complying with new or revised accounting standards is irrevocable. The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts and results of operations of the Company and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and judgments relied upon by management in preparing these consolidated financial statements include revenue recognition, reserves for excess and obsolete inventory, valuation of inventory and deferred inventory costs, the expensing and capitalization of software-related research and development costs, amortization and depreciation periods, the recoverability of net deferred tax assets, valuations of uncertain tax positions, warranty allowances, the valuation of equity instruments and stock-based compensation expense. Although the Company regularly reassesses the assumptions underlying these estimates, actual results could differ materially from these estimates. Changes in estimates are recorded in the period in which they become known. The Company bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances existing at the time such estimates are made . The COVID-19 pandemic presents various risks to the Company, not all of which the Company is able to fully evaluate or even to foresee at the current time, and which could have a material effect upon the estimates and judgments relied upon by management in preparing these consolidated financial statements. While the Company remains fully operational, during the year ended December 31, 2021, the effects of the COVID-19 pandemic on the global supply chain had a significant adverse effect on the Company’s financial results. In particular, certain of the Company’s products utilize components, whose availability was significantly exceeded by global demand. As a result, throughout 2021, the Company began to see shortages of supply that resulted in the Company’s inability to fulfill certain customer orders within normal lead times. This adversely impacted the Company’s revenue and operating results for year ended December 31, 2021. Additionally, shipping bottlenecks and delays negatively affected the Company’s ability to timely fulfill customer orders, thereby delaying its ability to consummate sales and recognize revenue. The Company also experienced, in some cases, significant increases in shipping costs. While the Company continues to work with its supply chain, contract manufacturers, logistics partners and customers to minimize the extent of such impacts, the Company expects the effects of global supply chain issues to continue and cannot predict when such effects will subside. This may prevent the Company from being able to fulfill its customers’ orders in a timely manner or at all, which could lead to one or more of its customers cancelling their orders. At this time the Company is neither able to estimate the extent of these impacts nor predict whether its efforts to minimize or contain them will be successful. The Company intends to continue to monitor its business very closely for any effects of COVID-19 for as long as necessary. Subsequent Event Considerations The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated as required. The Company has evaluated all subsequent events and determined that there are no material recognized or unrecognized subsequent events requiring disclosure in these consolidated financial statements. Cash, Cash Equivalents and Restricted Cash Cash and cash equivalents include all highly liquid investments maturing within three months from the date of purchase. As of December 31, 2021 and 2020, the Company’s cash and cash equivalents consisted of investments in money market mutual funds. Restricted cash as of December 31, 2021 and 2020 consisted of a certificate of deposit of $1,001 and $1,006, respectively, pledged as collateral for a stand-by letter of credit required to support a contractual obligation. Restricted cash as of also included cash of $2,100 pledged as collateral in connection with two letters of credit to support contractual obligations, as further discussed in Note 11, Debt. The following table is a reconciliation of cash, cash equivalents and restricted cash included in the accompanying consolidated balance sheets that sum to the total cash, cash equivalents and restricted cash included in the accompanying consolidated statements of cash flows. December 31, 2021 December 31, 2020 Cash and cash equivalents $ 154,703 $ 157,455 Restricted cash included in other assets 3,101 1,006 $ 157,804 $ 158,461 Accounts Receivable Accounts receivable are presented net of a provision for doubtful accounts, which is an estimate of amounts that may not be collectible. Accounts receivable for customer contracts with customary payment terms, which are one year or less, are recorded at invoiced amounts and do not bear interest. The Company may, in limited circumstances, grant payment terms longer than one year. Payments due beyond 12 months from the balance sheet date are recorded as non-current assets. The Company generally does not require collateral, but the Company may, in certain instances based on its credit assessment, require full or partial prepayment prior to shipment . Accounts receivable as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Current portion of accounts receivable, net: Accounts receivable, net $ 85,689 $ 93,480 Accounts receivable, extended payment terms 85 644 85,774 94,124 Accounts receivable, net of current portion: Accounts receivable, extended payment terms 115 143 $ 85,889 $ 94,267 The Company performs ongoing credit evaluations of its customers and, if necessary, provides a provision for doubtful accounts and expected losses. When assessing and recording its provision for doubtful accounts, the Company evaluates the age of its accounts receivable, current economic trends, creditworthiness of the customer, customer payment history, and other specific customer and transaction information. The Company writes off accounts receivable against the provision when it determines a balance is uncollectible and no longer actively pursues collection of the receivable. Adjustments to the provision for doubtful accounts are recorded as selling, general and administrative expenses in the consolidated statements of operations and comprehensive income (loss). A summary of changes in the provision for doubtful accounts for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Provision for doubtful accounts at beginning of year $ 58 $ 20 $ 410 Provisions and recoveries 59 38 560 Write-offs — — (950 ) Provision for doubtful accounts at end of year $ 117 $ 58 $ 20 As of December 31, 2021 and 2020, the Company concluded that all amounts due under extended payment terms were collectible and no reserve for credit losses was recorded. During the years ended December 31, 2021, 2020 and 2019, the Company did not provide a reserve for credit losses and did not write off any uncollectible receivables due under extended payment terms. Inventories The Company values inventories at the lower of cost or market value. The Company computes cost using the first-in first-out convention. Inventories are composed of hardware and related component parts of finished goods. The Company establishes provisions for excess and obsolete inventories after evaluating historical sales, future demand, market conditions, expected product life cycles, and current inventory levels to reduce such inventories to their estimated net realizable value. The Company makes such provisions in the normal course of business and charges them to cost of revenue in its consolidated statements of operations and comprehensive income (loss). The Company includes deferred inventory costs within inventory in its consolidated balance sheets. Deferred inventory costs represent the cost of products that have been delivered to the customer for which revenue associated with the arrangement has been deferred as a result of not meeting all of the required revenue recognition criteria, such as receipt of customer acceptance. The Company recognizes deferred inventory costs as cost of revenue in its consolidated statements of operations and comprehensive income (loss) when the related revenue is recognized. Property and Equipment The Company states property and equipment at historical cost less accumulated depreciation. The Company computes depreciation using the straight-line method over the estimated useful lives of the assets. The Company records leasehold improvements at cost with any reimbursement from the landlord being accounted for as deferred rent, which is amortized using the straight-line method over the lease term. The Company also includes costs for trial systems held and used by its customers pursuant to evaluation agreements within property and equipment. The Company depreciates trial systems held and used by its customers over the estimated useful life of such assets, which is two years. Whenever a trial system is sold to a customer and the selling price is recorded as revenue, the Company removes the related net book value of the trial system sold from property and equipment and records it as a cost of revenue. The Company expenses maintenance and repairs expenditures as incurred. Estimated useful lives of the respective property and equipment assets are as follows: Estimated Useful Life Computers and purchased software 3 – 4 years Leasehold improvements Shorter of lease term or 7 years Furniture and fixtures 6 – 8 years Machinery and equipment 3 – 10 years Building 40 years Building improvements 5 – 40 years Trial systems at customers’ sites 2 years Upon retirement or sale, the Company removes the cost of assets disposed of and the related accumulated depreciation from the accounts and any resulting gain or loss is included in income (loss) from operations. Impairment of Long-Lived Assets The Company evaluates its long-lived assets, which consist primarily of property and equipment and intangible assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. The Company measures recoverability of assets to be held and used by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the Company measures the impairment to be recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset, less the cost to sell. No events or changes in circumstances existed to require an impairment assessment during the years ended December 31, 2021, 2020 and 2019. Concentration of Risks Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents and accounts receivable. Cash and cash equivalents consist of demand deposits, savings accounts, money market mutual funds, and certificates of deposit with financial institutions, which may exceed Federal Deposit Insurance Corporation limits. The Company has not experienced any losses related to its cash and cash equivalents and does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company grants credit to customers in the ordinary course of business. Credit evaluations are performed on an ongoing basis to reduce credit risk, and no collateral is required from our customers. An allowance for uncollectible accounts is provided for those accounts receivable considered to be uncollectible based upon historical experience and credit evaluation. Due to these factors, no additional losses beyond the amounts provided for collection losses is believed by management to be probable in the Company’s accounts receivable. Significant customers are those that represent 10% or more of revenue or accounts receivable and are set forth in the following tables: Revenue Accounts Receivable, Net Year Ended December 31, December 31, 2021 2020 2019 2021 2020 Customer A 22 % 11 % * 21 % 14 % Customer B * * * 19 % * Customer C * * * 10 % * Customer D * 20 % 12 % * * Customer E * * 14 % * * * Less than 10% of total Certain of the components and subassemblies included in the Company’s products are obtained and manufactured from a single source or a limited group of suppliers. Although the Company seeks to reduce dependence on those single or limited source suppliers and manufacturers, the partial or complete loss of certain of these sources could have a material adverse effect on the Company’s operating results, financial condition and cash flows and damage its customer relationships. Goodwill and Intangible Assets Goodwill represents the excess purchase price over the estimated fair value of net assets acquired as of the acquisition date. Goodwill has been recorded in connection with the acquisition of NetComm on July 1, 2019 (refer to Note 3). The Company tests goodwill for impairment on an annual basis and between annual tests when impairment indicators are identified, and goodwill is written down when impaired. The Company performs its annual goodwill impairment test during its fourth quarter. For its annual goodwill impairment test, the Company operates under one reporting unit and the fair value of its reporting unit has been determined based on the Company’s enterprise value. As part of the annual goodwill impairment test, the Company has the option to perform a qualitative assessment to determine whether further impairment testing is necessary. Examples of events and circumstances that might indicate that the reporting unit’s fair value is less than its carrying amount include macro-economic conditions such as deterioration in the entity’s operating environment or industry or market considerations; entity-specific events such as increasing costs, declining financial performance, or loss of key personnel; or other events such as a sustained decrease in the stock price on either an absolute basis or relative to peers. If, as a result of its qualitative assessment, it is more likely than not (i.e., greater than 50% chance) that the fair value of the Company’s reporting unit is less than its carrying amount, the quantitative impairment test will be required. Otherwise, no further testing will be required. The Company completed its qualitative assessment and concluded that as of December 31, 2021 and 2020, it is not more likely than not that the fair value of the Company’s reporting unit is less than its carrying amount. The Company amortizes its acquired intangible assets subject to amortization using the straight-line method over their estimated useful lives, ranging from 3 to 10 years. Purchased software licenses are classified as intangible assets and are amortized using the straight-line method over their estimated useful lives, typically ranging from 3 to 4 years. The Company evaluates the recoverability of intangible assets periodically by taking into account events or circumstances that may warrant revised estimates of useful lives or that indicate the asset may be impaired. The Company considered potential impairment indicators of acquired intangible assets at December 31, 2021 and 2020 and noted no indicators of impairment. Product Warranties Substantially all of the Company’s products are covered by a warranty for software and hardware for periods ranging from 90 days to one year. In addition, in conjunction with customers’ renewals of maintenance and support contracts, the Company offers an extended warranty for periods typically of one to three years for agreed-upon fees. In the event of a failure of a hardware product or software covered by these warranties, the Company must repair or replace the software or hardware or, if those remedies are insufficient, and at the discretion of the Company, provide a refund. The Company’s warranty reserve, which is included in accrued expenses and other current liabilities in the consolidated balance sheets, reflects estimated material, labor and other costs related to potential or actual software and hardware warranty claims for which the Company expects to incur an obligation. The Company’s estimates of anticipated rates of warranty claims and the costs associated therewith are primarily based on historical information and future forecasts. The Company periodically assesses the adequacy of the warranty reserve and adjusts the amount as necessary. If the historical data used to calculate the adequacy of the warranty reserve are not indicative of future requirements, additional or reduced warranty reserves may be required. A summary of changes in the amount reserved for warranty costs for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Warranty reserve at beginning of year $ 2,354 $ 2,448 $ 926 Provisions 2,339 2,745 3,603 Acquired warranty reserve — — 1,867 Charges (2,301 ) (2,839 ) (3,948 ) Warranty reserve at end of year $ 2,392 $ 2,354 $ 2,448 Revenue Recognition Effective January 1, 2019, the Company adopted ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”) using the modified retrospective transition method. This method was applied to contracts that were not complete as of the date of initial application. The following is a summary of new and/or revised significant accounting policies affected by the Company’s adoption of ASC 606, which relate primarily to revenue and cost recognition. The Company generates revenue from sales of its products, along with associated maintenance, support and extended hardware warranty services, and to a lesser extent, from sales of professional services. Maintenance and support services include telephone support, bug fixes and unspecified software upgrades and updates provided on a when-and-if-available basis and/or extended hardware warranty. In its consolidated statements of operations and comprehensive income (loss), the Company classifies revenue from sales of cable, wireless and fixed telco products as product revenue, and revenue from maintenance and support and professional services as service revenue. In accordance with ASC 606, the Company recognizes revenue when a customer obtains control of promised products or services. The amount of revenue recognized reflects the consideration that the Company expects to be entitled to receive in exchange for these products or services. To achieve the core principle of this standard, the Company applies the following five steps: 1) Identify the contract with a customer 2) Identify the performance obligations in the contract 3) Determine the transaction price 4) Allocate the transaction price to performance obligations in the contract 5) Recognize revenue when or as the Company satisfies a performance obligation Performance Obligations The majority of the Company’s contracts with customers contain multiple performance obligations including products and maintenance services, and on a limited basis, professional services. For these contracts, the Company accounts for individual performance obligations separately if they are considered distinct. The Company’s cable, wireless and fixed telco products, maintenance services and professional services are considered distinct performance obligations. When multiple performance obligations exist in a customer contract, the Company allocates the transaction price to the separate performance obligations on a relative SSP basis. The Company determines SSP using its judgment and based on the best evidence available, which may include the selling price of products when sold on a standalone basis to similar customers in similar circumstances, or in the absence of standalone sales, taking into consideration the Company’s historical pricing practices by customer type, selling method (i.e., resellers or direct), and geographic-specific market factors. Product revenue Some of the Company’s cable, wireless and fixed telco products have both software and non-software (i.e., hardware) components that function together to deliver the products’ essential functionality. In these instances, the Company’s hardware cannot be used apart from the embedded software and is considered one distinct performance obligation. The Company recognizes revenue for both new and existing customers at a point in time when control of the products is transferred to the customer, which is typically when title and risk of loss have transferred and the right to payment is enforceable. The Company also earns revenue from the sale of perpetual software licenses and/or software-enabled capacity expansions. Revenue on perpetual software licenses and software-enabled capacity expansions for existing customers are also distinct performance obligations as they are separately identifiable and provide additional bandwidth capacity on hardware products already purchased by the customer. The Company recognizes revenue on perpetual software licenses and software-enabled capacity expansions when control is transferred, which is typically as the software entitlements are made available to the customer. When customer contracts require acceptance of product and services, the Company considers the nature of the acceptance provisions to determine if they are substantive or considered perfunctory to determine if these acceptance provisions impact the timing of revenue recognition. When acceptance provisions are considered substantive, the Company will defer revenue on all performance obligations in the contract subject to acceptance until acceptance has been received. The Company does not defer revenue when acceptance provisions are deemed perfunctory. Maintenance and Support Services and Professional Services Revenue Other than for certain of our CPE products, the Company generally sells its products with maintenance and support services, a distinct performance obligation that includes the stand-ready obligation to provide telephone support, bug fixes and unspecified software upgrades and updates provided on a when-and-if-available basis and/or extended hardware warranty. After the initial sale, customers may purchase annual renewals of support contracts. The Company’s telephone support and unspecified upgrades and updates are delivered over time and the Company therefore recognizes revenue ratably over the contract term, which is typically one year, but can be as long as five years. The Company also generates revenue from sales of professional services, such as installation, configuration and training. Professional services are a distinct performance obligation since the Company’s products are functional without these services and can generally be performed by the customer or a third party. The Company generally recognizes fee-based professional services delivered at a point in time as the professional services are completed and upon receipt of acceptance if applicable. The sale of the Company’s products generally includes a 90-day warranty on the software and a one-year Resellers and Sales Agents The Company markets and sells its products through its direct global sales force, supported by sales agents, and through resellers. The Company’s resellers receive an order from an end customer prior to placing an order with the Company, and the Company confirms the identification of or is aware of the end customer prior to accepting such order. The Company invoices the reseller an amount that reflects a reseller discount and records revenue based on the amount of the discounted transaction value. Aside from wireless and fixed telco hardware products, the Company’s resellers do not stock inventory received from the Company. When the Company transacts with a reseller, the contract is with the reseller and not with the end customer. Whether the Company transacts business with and receives the order directly from the reseller or a customer, its revenue recognition policy and resulting pattern of revenue recognition for the order are the same. The Company has assessed whether it is principal (i.e., reports revenue on a gross basis) or agent (i.e., reports revenues on a net basis) by evaluating whether it has control of the good or service before it is transferred to the reseller. As the Company controls the promised good or service before transferring it to the reseller, it acts as the principal in the transaction. Accordingly, the Company reports revenues on a gross basis. The Company also uses sales agents that assist in the sales process with certain customers, primarily located in the Latin America and Asia-Pacific regions. Sales agents are not resellers. If a sales agent is engaged in the sales process, the Company receives the order directly from the end customer and sells the products and services directly to the end customer, and the Company pays a commission to the sales agent, calculated as a percentage of the related transaction value. Accounting considerations related to sales agent commissions are discussed in the “Costs to Obtain or Fulfill a Contract” section below. Costs to Obtain or Fulfill a Contract The Company capitalizes commission expenses paid to internal sales personnel and sales agent commissions that are incremental to obtaining customer contracts, for which the related revenue is recognized over a future period greater than 12 months. These costs are incurred on initial sales of product, professional services and maintenance and support contract renewals. The Company defers these costs and amortizes them over the period of benefit, which is generally considered to be the contract term. The Company has elected to use the practical expedient, allowing the Company to recognize the incremental costs of obtaining a contract as an expense when incurred if the amortization period of the asset that the entity otherwise would have recognized is one year or less. Commissions paid relating to maintenance and support contract renewals of twelve months or less are expensed as incurred as commissions paid on renewals are commensurate with commissions paid on initial sales transactions. Costs to obtain a contract for professional services contracts are expensed as incurred in accordance with the practical expedient as the contractual period of our professional services contracts are one year or less. The Company periodically reviews the carrying amount of capitalized contract costs to determine whether events or changes in circumstances have occurred that could impact the period of benefit. Deferred Revenue The Company recognizes amounts billed in excess of revenue recognized as deferred revenue. Deferred revenue includes customer deposits, amounts billed for maintenance and support services contracts in advance of services being performed, amounts for trade-in right liabilities and amounts related to contracts that have been deferred as a result of not meeting the required revenue recognition criteria as of the end of the reporting period. The Company reports deferred revenue expected to be recognized as revenue more than one year subsequent to the balance sheet date within long-term liabilities in the consolidated balance sheets. The Company defers recognition of direct costs, such as cost of goods and services, until recognition of the related revenue. The Company classifies such costs as current assets if the related deferred revenue is classified as current and as non-current assets if the related deferred revenue is classified as non-current. Other Revenue Recognition Policies The Company’s customary payment terms are generally 90 days or less. The Company has elected to apply the practical expedient that allows an entity to not adjust the promised amount of consideration in customer contracts for the effect of a significant financing component when the period between the transfer of product and services and payment of the related consideration is less than one year. If the Company provides extended payment terms that represent a significant financing component, the Company adjusts the amount of promised consideration for the time value of money using an appropriate discount rate and recognizes interest income separate from the revenue recognized on contracts with customers. During the years ended December 31, 2021, 2020 and 2019, the Company recorded $20, $64 and $160, respectively, in interest income in its consolidated statements of operations and comprehensive income (loss) related to arrangements with customers that were determined to have a significant financing component. In limited instances, the Company has offered future rebates to customers based on a fixed or variable percentage of actual sales volumes over specified periods. The future rebates earned based on the customer’s purchasing from the Company in one period may be used as credits to be applied by them against accounts receivable due to the Company in later periods. The Company accounts for these future rebates as variable consideration and reduces the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will occur when the variable consideration is resolved. The Company estimates the reduction of the transaction price based on historical activity and other relevant factors and recognizes it when the Company recognizes revenue for the transfer of goods and services to the customer on which the future rebate was earned. Other forms of contingent revenue or variable consideration are infrequent. The Company excludes any taxes assessed by a governmental authority that are directly imposed on a revenue-producing transaction (e.g., sales, use and value added taxes) from its transaction price. The Company records b illings to customers for reimbursement of out-of-pocket expenses, including travel, lodging and meals, as revenue, and the associated costs incurred by the Company as cost of revenue. Revenue related to the reimbursement of out-of-pocket costs are accounted for as variable consideration . The Company accounts for any shipping and handling activities as a fulfilment cost rather than an additional promised service. The Company records shipping and handling billed to customers as an offset to cost of revenue. Stock-Based Compensation The Company measures stock options and other stock-based awards granted to employees and directors based on the fair value on the date of grant and recognizes compensation expense of those awards, net of estimated forfeitures, over the requisite service period, which is generally the vesting period of the respective award. Generally, the Company issues stock options with only service-based vesting conditions and records the expense for these awards using the straight-line method. The Company classifies stock-based compensation expense in its consolidated statements of operations and comprehensive income (loss) in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. The Company recognizes compensation expense for only the portion of awards that are expected to vest. In developing a forfeiture rate estimate, the Company has considered its historical experience to estimate pre-vesting forfeitures for service-based awards. The impact of a forfeiture rate adjustment will be recognized in full in the period of adjustment, and if the actual forfeiture rate is materially different from the Company’s estimate, the Company may be required to record adjustments to stock-based compensation expense in future periods. The Company estimates the fair value of each stock option and stock appreciation right, or SAR, grant on the date of grant using the Black-Scholes option pricing model. The Company was a private company until December 14, 2017 and lacked sufficient company-specific histori

Business Acquisition

Business Acquisition	12 Months Ended
	Dec. 31, 2021
Business Combinations [Abstract]
Business Acquisition	3. Business Acquisition On July 1, 2019, the Company acquired 100% of the equity interests in NetComm for cash consideration of $161,963 AUD ($112,674 USD, based on an exchange rate of USD $0.700 per AUD $1.00 on July 1, 2019) The Company allocated $44,000 to identifiable intangible assets consisting of developed technology, amortized over seven years using a straight-line amortization method; customer relationships, amortized over ten years using a straight-line amortization method; and a trade name, amortized over three years using a straight-line amortization method. The weighted-average life of the identifiable intangible assets recognized from the Acquisition was 8.2 years. The intangible assets acquired in the Acquisition are not deductible for tax purposes. NetComm is a global leader in the development of fixed wireless and fiber extension broadband solutions. With the Acquisition, the Company added to its product portfolio highly competitive 4G and 5G fixed wireless access products and fixed broadband customer premise equipment for public and private service providers and enterprise networks. This factor contributed to a purchase price in excess of fair value of NetComm’s net tangible and intangible assets, leading to the recognition of goodwill of $50,177. Additional factors that contributed to the establishment of goodwill included the strategic benefit of expanding the breadth of the Company’s product offerings; the value of NetComm’s highly trained work force; the expected revenue growth over time that is attributable to increased market penetration from future products and customers, and cross-selling by the sales force; and the synergies expected to result from reducing redundant infrastructure such as corporate costs and field operations. The goodwill acquired in the Acquisition is not deductible for tax purposes. The results of operations of NetComm have been included in the Company’s consolidated statements of operations and comprehensive income (loss) since the completion of the Acquisition on July 1, 2019. For the year ended December 31, 2019, NetComm contributed $75,769 to the Company’s consolidated net revenues and $1,424 in after tax losses to the Company’s consolidated net loss. Transactions costs of $3,494 are included in selling, general and administrative expenses in the consolidated statements of operations and comprehensive income (loss) for the year ended December 31, 2019.

Goodwill and Intangibles

Goodwill and Intangibles	12 Months Ended
	Dec. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangibles	4. Goodwill and Intangibles Intangible Assets Intangible assets, net consisted of intangible assets resulting from the acquisition of NetComm and purchased software to be used in our products. Intangible assets, net consisted of the following at December 31, 2021 and 2020, respectively: As of December 31, 2021 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Developed technology 25,000 (8,930 ) 16,070 Customer relationships 18,000 (4,500 ) 13,500 Trade name 1,000 (830 ) 170 Purchased Software 1,832 (428 ) 1,404 Totals as of December 31, 2021 $ 45,832 $ (14,688 ) $ 31,144 As of December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Developed technology 25,000 (5,358 ) 19,642 Customer relationships 18,000 (2,700 ) 15,300 Trade name 1,000 (498 ) 502 Purchased Software 432 (32 ) 400 Totals as of December 31, 2020 $ 44,432 $ (8,588 ) $ 35,844 As of December 31, 2021, amortization expense on existing intangible assets for the next five years and beyond is summarized as follows: Year Ending December 31, 2022 $ 5,963 2023 5,764 2024 5,660 2025 5,651 2026 3,606 Thereafter 4,500 $ 31,144 A Year Ended December 31, 2021 2020 Product cost of revenue $ 3,572 $ 3,571 Research and development 396 32 Selling, general and administrative 2,132 2,133 Totals $ 6,100 $ 5,736 Goodwill The Company’s goodwill is the result of its acquisition of NetComm on July 1, 2019 and represents the excess of purchase price over the estimated fair value of net assets acquired. The changes in the carrying value of goodwill are as follows: Carrying Value of Goodwill Balance at December 31, 2019 $ 50,347 Adjustment recorded to preliminary purchase price allocation (170 ) Balance at December 31, 2020 $ 50,177 There has been no change to the $50,177 carrying amount of goodwill since December 31, 2020.

Inventory

Inventory	12 Months Ended
	Dec. 31, 2021
Inventory Disclosure [Abstract]
Inventory	5. Inventory Inventory as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Raw materials $ 53,934 $ 50,904 Work in process — 19 Finished goods: Manufactured finished goods 29,597 49,764 Deferred inventory costs 1,297 517 $ 84,828 $ 101,204 The decrease in inventory balances was due to shortages of supply due to supply chain impacts of COVID-19, as demand for certain of the Company’s component parts has increased globally in the year ended December 31, 2021.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2021
Property Plant And Equipment [Abstract]
Property and Equipment	6. Property and Equipment Property and equipment as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Computers and purchased software $ 25,775 $ 24,865 Leasehold improvements 4,198 4,148 Furniture and fixtures 2,672 2,644 Machinery and equipment 37,325 36,701 Land 3,091 3,091 Building 4,765 4,765 Building improvements 7,291 7,244 Trial systems at customers’ sites 3,848 5,300 88,965 88,758 Less: Accumulated depreciation and amortization (65,457 ) (59,878 ) $ 23,508 $ 28,880 During the years ended December 31, 2021, 2020 and 2019, the Company transferred trial systems into inventory from property and equipment with values of $1,452, $1,259 and $502, respectively, net of transfers of trial systems to cost of revenue. In addition, during the years ended December 31, 2021, 2020 and 2019, the Company transferred $993, $805 and $261 of equipment from inventory into property and equipment, respectively. Total depreciation and amortization expense on property and equipment totaled $9,580, $12,234, and $11,870 for the years ended December 31, 2021, 2020 and 2019, respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2021
Payables And Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	7. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Accrued compensation and related taxes $ 21,751 $ 22,785 Accrued warranty (see Note 2) 2,392 2,354 Inventory-related accruals 8,391 855 Other accrued expenses 8,848 13,799 $ 41,382 $ 39,793

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	8. Fair Value Measurements The Company’s cash equivalents include money market mutual funds, which are valued using Level 1 inputs in the fair value hierarchy. The Company’s restricted cash consists of certificates of deposit, which are valued using Level 2 inputs in the fair value hierarchy. The Company’s foreign currency forward contracts are valued using Level 2 inputs in the fair value hierarchy. The Company values its SARs using Level 3 inputs in the fair value hierarchy based on management’s judgment and the assumptions set forth in Note 13 as there is no market activity to derive an estimate of their fair value. The Company records changes in the fair value of SARs in operating expenses in the consolidated statements of operations and comprehensive income (loss). The following tables present information about the fair value of the Company’s financial assets and liabilities as of December 31, 2021 and 2020 and indicate the level of the fair value hierarchy utilized to determine such fair values: Fair Value Measurements as of December 31, 2021 Using: Level 1 Level 2 Level 3 Total Assets: Certificates of deposit—restricted cash $ — $ 1,001 $ — $ 1,001 Money market mutual funds 93,792 — — 93,792 Forward currency forward contract — 5 — 5 $ 93,792 $ 1,006 $ — $ 94,798 Liabilities: SARs $ — $ — $ 358 $ 358 $ — $ — $ 358 $ 358 Fair Value Measurements as of December 31, 2020 Using: Level 1 Level 2 Level 3 Total Assets: Certificates of deposit—restricted cash — 1,006 — 1,006 Money market mutual funds 114,404 — — 114,404 $ 114,404 $ 1,006 $ — $ 115,410 Liabilities: SARs $ — $ — $ 493 $ 493 $ — $ — $ 493 $ 493 During the years ended December 31, 2021, 2020 and 2019 there were no The liability for SARs in the table above consists of the fair value of the SARs granted to the Company’s employees. The fair values of the SARs are based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The Company’s valuation of these SARs utilized the Black-Scholes option-pricing model, which incorporates assumptions and estimates to determine their fair values (see Note 2). The Company assesses these assumptions and estimates on a quarterly basis as additional information impacting the assumptions is obtained. The Company recognizes changes in the fair value of the SARs liability as stock-based compensation expense in the consolidated statements of operations and comprehensive income (loss). The following table provides a summary of changes in the fair values of the Company’s SARs liability, for which fair value is determined by Level 3 inputs: Year Ended December 31, 2021 2020 2019 Fair value at beginning of the year $ 493 $ 264 $ 1,387 Change in fair value — 229 (1,123 ) Exercises (135 ) — — Fair value at end of year $ 358 $ 493 $ 264 The Company’s cash, cash equivalents and restricted cash as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Cash $ 60,911 $ 43,051 Cash equivalents and restricted cash: Restricted cash 3,101 1,006 Money market mutual funds 93,792 114,404 Total cash equivalents and restricted cash 96,893 115,410 Total cash, cash equivalents and restricted cash $ 157,804 $ 158,461

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2021
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative Instruments	9. Derivative Instruments The Company has certain international customers that are billed in foreign currencies. To mitigate the volatility related to fluctuations in the foreign exchange rates for accounts receivable denominated in foreign currencies, the Company enters into foreign currency forward contracts. As of December 31, 2021, the Company had a foreign currency forward contract outstanding with a notional amount totaling 241 Euros related to the Company’s Irish subsidiary. This contract will mature during the first quarter of 2022. As of December 31, 2020, The Company’s foreign currency forward contracts described above economically hedged certain risks, but were not designated as hedges for financial reporting purposes, and accordingly, the Company recorded all changes in the fair value of the derivative instruments as unrealized foreign currency transaction gains or losses and included them in the consolidated statements of operations and comprehensive income (loss) as a component of other income (expense). The Company records derivative instruments in the consolidated balance sheet at their fair values. As of December 31, 2021, the Company recorded an The Company also faces exposure to foreign currency exchange rate fluctuations, as a certain portion of its expenses are denominated in currencies other than U.S. dollars. In certain instances, the Company utilizes forward contracts to hedge against foreign currency fluctuations. These contracts are used to minimize foreign gains or losses, as the gains or losses on the derivative are intended to offset the losses or gains on the underlying exposure. The Company does not engage in foreign currency speculation. The Company designed its foreign currency risk management strategy principally to mitigate the potential financial impact of changes in the value of transactions and balances denominated in foreign currencies resulting from changes in foreign currency exchange rates. The Company may enter into cash flow hedges that utilize foreign currency forward contracts to hedge specific forecasted transactions of its foreign subsidiaries with the goal of protecting its budgeted expenses against foreign currency exchange rate changes compared to its budgeted rates. During the year ended December 31, 2020, the Company settled two cash flow hedges with notional amounts of 8,500 AUD and 5,000 AUD to hedge certain Australian Dollar cash flows incurred during the period. The Company reclassified the amount of $752 from other comprehensive income (loss) for the year ended December 30, 2020. The Company recognized the full amount of the fair value of the derivatives on the settlement date of $1,613 proportionately as $124 cost of goods sold, $890 research and development expense and $599 selling, general and administrative expense in the consolidated statement of comprehensive income for the year ended December 31, 2020. The Company did not have any cash flow hedges outstanding as of December 31, 2021 or 2020.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes Income before the provision for (benefit from) income taxes for the years ended December 31, 2021, 2020 and 2019 consisted of the following: Year Ended December 31, 2021 2020 2019 United States $ (32,059 ) $ (32,755 ) $ (40,055 ) Foreign 35,553 42,504 15,640 $ 3,494 $ 9,749 $ (24,415 ) The provision for (benefit from) income taxes for the years ended December 31, 2021, 2020 and 2019 consisted of the following: Year Ended December 31, 2021 2020 2019 Current income tax provision (benefit): Federal $ (7,709 ) $ (24,409 ) $ 4,698 State (57 ) 228 (121 ) Foreign 8,984 11,655 (427 ) Total current income tax provision (benefit) 1,218 (12,526 ) 4,150 Deferred income tax provision (benefit): Federal 72 171 18,387 State — 97 5,100 Foreign (1,003 ) (2,794 ) (3,846 ) Total deferred income tax provision (benefit) (931 ) (2,526 ) 19,641 Total income tax provision (benefit) $ 287 $ (15,052 ) $ 23,791 A reconciliation of the U.S. federal statutory rate to the Company’s effective income tax rate for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % State taxes, net of federal tax benefit (61.9 ) (6.8 ) 9.8 Research and development tax credits 494.4 (37.6 ) 10.3 Permanent differences (20.6 ) (11.5 ) (1.6 ) Foreign tax rate differential (42.6 ) 7.3 10.2 Stock-based compensation (61.8 ) 8.6 5.0 Foreign taxes withheld 79.9 23.1 (9.6 ) Rate impact from CARES Act (69.2 ) (63.9 ) — Global intangible low-taxed income 75.3 35.7 (4.1 ) Withholding tax on repatriation of accumulated earnings of foreign subsidiaries 1.9 1.0 (0.1 ) Valuation allowance on deferred tax assets 146.2 (146.9 ) (144.2 ) Other, net 8.2 (7.5 ) 13.9 Foreign derived intangible income — — 3.9 Research and development costs (254.6 ) 20.0 (4.3 ) Uncertain tax positions (343.4 ) (3.2 ) (7.1 ) Non-deductible executive compensation expense 35.4 6.3 (0.5 ) Effective income tax rate 8.2 % (154.4 )% (97.4 )% Certain amounts in the above table reported in previous years have been reclassified to conform to the presentation for the fiscal year ended December 31, 2021. The income tax effect of each type of temporary difference and carryforward as of December 31, 2021 and 2020 was as follows: December 31, 2021 2020 Deferred tax assets: Stock compensation $ 4,050 $ 4,710 Tax credit carryforwards 12,463 13,138 Net operating loss carryforward 4,695 1,504 Capitalized research and development costs 8,322 9,710 Inventory valuation 4,070 2,169 Accrued liabilities and reserves 5,680 4,825 Deferred revenue 295 796 Interest expense 2,436 — Other 607 724 Total deferred tax assets 42,618 37,576 Valuation Allowance (29,457 ) (24,463 ) Deferred tax assets, net of valuation allowance 13,161 13,113 Deferred tax liabilities: Depreciation (1,488 ) (2,092 ) Amortization (8,938 ) (10,932 ) Deferred costs (4,946 ) (3,444 ) Withholding tax on unremitted earnings (2,721 ) (2,650 ) Prepaid expenses (260 ) (127 ) Total deferred tax liabilities (18,353 ) (19,245 ) Net deferred tax liabilities $ (5,192 ) $ (6,132 ) Certain amounts in the above table reported in previous years have been reclassified to conform to the presentation as of December 31, 2021. The Company has determined that it is more likely than not its net U.S. deferred tax assets will not be realized. As of December 31, 2021, the Company maintains a valuation allowance of $28,190 against its net U.S. deferred tax assets, an increase of $3,727 during the year ended December 31, 2021. Additionally, the Company maintains a valuation allowance of $1,267 against its net foreign deferred tax assets in certain jurisdictions, which were established during 2021. The change in valuation allowance is primarily due to operating results of the Company in 2021, including an increase in the Company’s U.S. research and development credit and interest limitation deferred tax assets. The Company does not anticipate sufficient taxable income or tax liability to utilize its net U.S. and certain foreign deferred tax assets in the foreseeable future. The Company will continue to monitor the realizability of its deferred tax assets and take into account multiple factors, including recent operating results, existing taxable temporary differences, future taxable income projections and tax planning strategies. The Company intends to maintain a valuation allowance on its net U.S. and certain foreign deferred tax assets until there is sufficient positive evidence to support the reversal of all or some portion of the valuation allowances. The release of all, or a portion of, the valuation allowance would result in the recognition of certain deferred tax assets and a decrease to income tax expense for the period the release is recorded. On March 27, 2020, the Coronavirus Aid, Relief and Economic Security (“CARES Act”) was signed into law. Among other things, the CARES Act permits net operating loss (“NOL”) carryovers and carrybacks to offset 100 years beginning in 2019 and 2020. The modifications to Section 163(j) increase the allowable business interest deduction from 30 % of adjusted taxable income to 50 % of adjusted taxable income. Effective for taxable years beginning after January 1, 2018, taxpayers are subjected to the GILTI provisions. The GILTI provisions require the Company to currently recognize in U.S. taxable income a deemed dividend inclusion of foreign subsidiary earnings in excess of an allowable return on the foreign subsidiary’s tangible assets. The ability to benefit from a deduction and foreign tax credits against a portion of the GILTI income may be limited under the GILTI rules as a result of the utilization of net operating losses, foreign sourced income, and other potential limitations within the foreign tax credit calculation. The Company made an accounting policy election, as allowed by the SEC and FASB, to recognize the impacts of GILTI within the period incurred. During the years ended December 31, 2021, 2020 and 2019, the Company recorded income tax charges of $2,630, $3,483 and $942, respectively, related to GILTI. As a result of foreign tax law developments occurring during 2021, the Company recorded a tax benefit of $2,869 to conform its historical treatment of the impacted items to the newly issued guidance. As of December 31, 2021, the Company had federal NOL carryforwards of $714 that can be carried forward indefinitely and state NOL carryforwards of $35,576, of which $21,507 will begin to expire in 2031 and $14,069 can be carried forward indefinitely. As of December 31, 2021, the Company had available federal and state research and development tax credit carryforwards of $1,293 and $12,503, respectively, which begin to expire in 2030. Management believes that it is more likely than not that the Company will not realize the benefit of its federal and state net operating losses and research and development tax credits and thus has recorded a valuation allowance against these deferred tax assets. As of December 31, 2021, the Company had foreign net operating loss carryforwards of $9,745, of which $2,931 will begin to expire in 2024 and $6,814 can be carried forward indefinitely. As of December 31, 2021, substantially all of the Company’s unremitted earnings have been taxed through either the deemed repatriation tax or as GILTI income. Of the total amount of undistributed earnings, $27,211 is not indefinitely reinvested and the Company has recorded a $2,721 deferred tax liability related to its withholding taxes associated with such undistributed earnings. The Company records interest and penalties related to uncertain tax positions in its consolidated statements of operations and comprehensive income (loss) within other income (expense). Interest and penalties included in the consolidated statements of operations and comprehensive income (loss) were ($2,012), $614 and $1,278 for the years ended December 31, 2021, 2020 and 2019, respectively. The Company recorded a liability for interest and penalties of $248 and $2,260 as of December 31, 2021 and 2020, respectively. As of December 31, 2021, the amount of uncertain tax benefits that, if recognized, would impact the effective income tax rate was $5,359. The aggregate changes in the balance of gross uncertain tax positions, which excludes interest and penalties, for the years ended December 31, 2021, 2020 and 2019 were as follows: Balance at December 31, 2018 $ 2,746 Settlement/decreases related to tax positions taken during prior years (49 ) Increases related to tax positions taken during prior years 18,434 Increases related to tax positions taken during the current year 364 Balance at December 31, 2019 21,495 Expiration of statute of limitations (1,174 ) Settlement/decreases related to tax positions taken during prior years (2,815 ) Increases related to tax positions taken during prior years 155 Increases related to tax positions taken during the current year 249 Balance at December 31, 2020 17,910 Decreases related to tax positions taken during prior years (13,510 ) Increases related to tax positions taken during prior years 1,190 Increases related to tax positions taken during the current year 402 Balance at December 31, 2021 $ 5,992 The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction as well as various states and foreign jurisdictions. The Company and certain subsidiaries have tax years that remain open and are subject to examination by tax authorities in the following major taxing jurisdictions: United States for tax years 2018 through 2021, Ireland for tax years 2017 through 2021, China for tax years 2011 through 2021 and Australia for tax years 2017 through 2021. In addition, U.S. federal tax years from 2014 through 2017 are open to the extent of refund claims associated with CARES Act NOL carrybacks. The Company files income tax returns on a combined, unitary, or stand-alone basis in multiple state and local jurisdictions, which generally have statutes of limitations from three to four years. If any issues addressed in the Company’s tax audits are resolved in a manner not consistent with management’s expectations, the Company would be required to adjust its provision for income tax in the period such resolution occurs. The Company’s unrecognized tax benefits could change up to $3,129 in the next 12 months due to the expiration of the statute of limitations.

Debt

Debt	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Debt	11. Debt The aggregate principal amount of debt outstanding as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Term loans $ 278,225 $ 288,000 Revolving credit facility — 6,500 Total principal amount of debt outstanding $ 278,225 $ 294,500 Current and non-current debt obligations reflected in the consolidated balance sheets as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Current liabilities: Term loans $ 3,000 $ 9,775 Revolving credit facility — 6,500 Current portion of principal payment obligations 3,000 16,275 Unamortized debt issuance costs, current portion (1,076 ) (1,104 ) Current portion of long-term debt, net of unamortized debt issuance costs $ 1,924 $ 15,171 Non-current liabilities: Term loans $ 275,225 $ 278,225 Unamortized debt issuance costs, non-current portion (1,032 ) (2,140 ) Long-term debt, net of current portion and unamortized debt issuance costs $ 274,193 $ 276,085 As of December 31, 2021, aggregate minimum future principal payments of the Company’s debt are summarized as follows: Year Ending December 31, 2022 $ 3,000 2023 275,225 Thereafter — $ 278,225 Term Loan and Revolving Credit Facilities On December 20, 2016, the Company entered into a credit agreement with JPMorgan Chase Bank, N.A., as administrative agent, various lenders and JPMorgan Chase Bank, N.A. and Barclays Bank PLC providing for (i) a term loan facility of $300,000 and (ii) a revolving credit facility of up to $25,000 in revolving credit loans and letters of credit. As of December 31, 2021 and 2020, $278,225 and $288,000 in principal amount, respectively, were outstanding under the term loan facility (the “Term Loan”) and as of December 31, 2020, the Company had outstanding borrowings under the revolving credit facility of $6,500 that were drawn down during the year ended December 31, 2020. The outstanding borrowings under the revolving credit facility were repaid in full on October 25, 2021, and the revolving credit facility matured on December 20, 2021. As of December 31, 2020, the Company had also used $1,454 of availability under the revolving credit facility for two stand-by letters of credit, one which served as collateral to one of the Company’s customers pursuant to a contractual obligation and one which served as collateral for operating leases in Australia. Upon maturity of the revolving credit facility on December 20, 2021, the Company entered into two new letters of credit, backed by cash collateral of $2,100, to serve as collateral for these obligations. These amounts were included in other assets in the consolidated balance sheets as of December 31, 2021. Borrowings under the facilities bear interest at a floating rate, which can be either a Eurodollar rate plus an applicable margin or, at the Company’s option, a base rate (defined as the highest of (x) the JPMorgan Chase, N.A. prime rate, (y) the federal funds effective rate, plus one-half percent (0.50%) per annum and (z) a one-month Eurodollar rate plus 1.00% per annum) plus an applicable margin. The applicable margin for borrowings under the Term Loan is 4.00% per annum for Eurodollar rate loans (subject to a 1.00% per annum interest rate floor) and 3.00% per annum for base rate loans. The applicable margin for borrowings under the revolving credit facility was 1.75% per annum for Eurodollar rate loans and 0.75% per annum for base rate loans, subject to reduction based on the Company’s maintaining of specified net leverage ratios. The interest rates payable under the facilities are subject to an increase of 2.00% per annum during the continuance of any payment default. For Eurodollar rate loans, the Company may select interest periods of one, three or six months or, with the consent of all relevant affected lenders, twelve months. Interest will be payable at the end of the selected interest period, but no less frequently than every three months within the selected interest period. Interest on any base rate loan is not set for any specified period and is payable quarterly. The Company has the right to convert Eurodollar rate loans into base rate loans and the right to convert base rate loans into Eurodollar rate loans at its option, subject, in the case of Eurodollar rate loans, to breakage costs if the conversion is effected prior to the end of the applicable interest period. As of December 31, 2021 and 2020, the interest rate on the Term Loan was 5.00% per annum, which was based on a one-month and six-month Eurodollar rate, respectively, of 1.00% per annum plus the applicable margin of 4.00% per annum for Eurodollar rate loans. Upon entering into the Term Loan, the Company incurred debt issuance costs of $7,811, which were initially recorded as a reduction of the debt liability and are being amortized to interest expense using the effective interest method from the issuance date of the Term Loan until the maturity date. The Company made principal payments of $9,775 under the Term Loan during the year ended December 31, 2021 and $3,000 under the Term Loan during each of the years ended December 31, 2020 and 2019. Interest expense, including the amortization of debt issuance costs, totaled $15,519, $16,493 and $19,728 for the years ended December 31, 2021, 2020 and 2019, respectively. The revolving credit facility also required payment of quarterly commitment fees at a rate of 0.25% per annum on the difference between committed amounts and amounts actually borrowed under the facility and customary letter of credit fees. For the years ended December 31, 2021, 2020 and 2019, interest expense related to the fee for the unused amount of the revolving credit facility totaled $46, $52 and $59, respectively. The Term Loan matures on December 20, 2023 and is subject to amortization in equal quarterly installments, which commenced on March 31, 2017, of principal in an annual aggregate amount equal to 1.0% of the original principal amount of the Term Loan of $300,000, with the remaining outstanding balance payable at the date of maturity. Voluntary prepayments of principal amounts outstanding under the Term Loan are permitted at any time; however, if a prepayment of principal is made with respect to a Eurodollar loan on a date other than the last day of the applicable interest period, the Company is required to compensate the lenders for any funding losses and expenses incurred as a result of the prepayment. Prior to the revolving credit facility maturity date, funds borrowed under the revolving credit facility could have been borrowed, repaid and reborrowed, without premium or penalty. In addition, the Company is required to make mandatory prepayments under the facilities with respect to (i) 100% of the net cash proceeds from certain asset dispositions (including casualty and condemnation events) by the Company or certain of its subsidiaries, subject to certain exceptions and reinvestment provisions, (ii) 100% of the net cash proceeds from the issuance or incurrence of any additional debt by the Company or certain of its subsidiaries, subject to certain exceptions, and (iii) 50% of the Company’s excess cash flow, as defined in the credit agreement, subject to reduction upon its achievement of specified performance targets. In accordance with these provisions, based on the results for the year ended December 31, 2020, a mandatory prepayment of $6,775 was paid on April 2, 2021. This amount was included in the current portion of long-term debt, net of unamortized debt issuance costs on the consolidated balance sheet as of December 31, 2020. Based on results for the year ended December 31, 2021, no mandatory prepayment will be required in 2022. The facilities are secured by, among other things, a first priority security interest, subject to permitted liens, in substantially all of the Company’s assets and all of the assets of certain of its subsidiaries and a pledge of certain of the stock of certain of its subsidiaries, in each case subject to specified exceptions. The facilities contain customary affirmative and negative covenants, including certain restrictions on the Company’s ability to pay dividends, and, with respect to the revolving credit facility which expired on December 20, 2021, a financial covenant requiring the Company to maintain a specified total net leverage ratio in the event that on the last day of any fiscal quarter the Company has utilized more than 30% of its borrowing capacity under the facility. The Company was in compliance with all covenants as of December 31, 2021 and 2020. Commercial Mortgage Loan On July 1, 2015, the Company entered into a commercial mortgage loan agreement in the amount of $7,950 (the “Mortgage Loan”). Borrowings under the Mortgage Loan bore interest at a rate of 3.5% per annum and were repayable in 60 monthly installments of $46, consisting of principal and interest based on a 20-year amortization schedule. The remaining amount of unpaid principal under the Mortgage Loan was paid on the maturity date of July 1, 2020 utilizing the Company’s revolving credit facility. Upon entering into the Mortgage Loan, the Company incurred debt issuance costs of $45, which the Company initially recorded as a direct deduction from the debt liability and amortized to interest expense using the effective interest method from issuance date of the loan until the maturity date. The Company made principal payments under the Mortgage Loan of $6,644 and $314 during the years ended December 31, 2020 and 2019, respectively. Interest expense, including the amortization of debt issuance costs, totaled $120 and $249 for the years ended December 31, 2020 and 2019, respectively.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Stockholders' Equity	12. Stockholders’ Equity The board of directors, on five separate occasions, declared a special dividend to the holders of common stock and preferred stock of record at that time. In connection with these special dividends, the board of directors also approved cash payments to be made to holders of the Company’s stock options, SARs and restricted stock units (“RSUs”) as equitable adjustments to the holders of such instruments in accordance with the provisions of the Company’s equity incentive plans. These equitable adjustment payments are equal to an amount per share multiplied by the net number of shares subject to outstanding equity awards after applying the treasury stock method. The below table provides details of these equitable adjustment payments: Equitable Adjustment Payments During the Year Ended Equitable Adjustment Liability(1) Dividend Declaration Dates Equitable Adjustment per share Year of Final Vesting December 31, 2021 December 31, 2020 December 31, 2019 As of December 31, 2021 As of December 31, 2020 November 30, 2017 $ 0.5802 2021 $ 44 $ 148 $ 426 — $ 30 May 10, 2017 1.1774 2021 52 178 618 — 31 December 27, 2016 2.3306 2020 2 303 1,286 — 2 June 17, 2016 0.5891 2020 — 54 259 — — November 30, 2014 0.3835 2018 — — 1 — — Total $ 98 $ 683 $ 2,590 $ — $ 63 (1) Net of estimated forfeitures. Amounts are included in accrued expenses and other current liabilities in the accompanying consolidated balance sheets.

Stock-based Compensation

Stock-based Compensation	12 Months Ended
	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based Compensation	13. Stock-based Compensation 2011 Stock Incentive Plan The Company’s 2011 Stock Incentive Plan (the “2011 Plan”) provided for the Company to sell or issue common stock or restricted common stock, or to grant qualified incentive stock options, nonqualified stock options, SARs, RSUs or other stock-based awards to the Company’s employees, officers, directors, advisers and outside consultants. The 2011 Plan was administered by the board of directors, or at the discretion of the board of directors, by a committee of the board. The exercise prices, vesting and other restrictions were determined at the discretion of the board of directors, or a committee of the board, if so delegated, except that the exercise price per share of stock options could not be less than 100% of the fair market value of common stock on the date of grant and the term of the stock option could not be greater than ten years. The stock options generally vest over a four-year ten years The 2011 Plan was terminated for the purpose of making new grants in December 2017, and the remaining 2,855 shares available for issuance under the 2011 Plan at that time were transferred to the 2017 Plan. Awards outstanding under the 2011 Plan at the time of the 2011 Plan’s termination will continue to be governed by their existing terms. The shares of common stock underlying any awards that are forfeited, canceled, repurchased or otherwise terminated by the Company under the 2011 Plan will be added back to the shares of common stock available for issuance under the 2017 Plan. 2017 Stock Incentive Plan On November 17, 2017, the Company’s board of directors adopted, and on November 30, 2017, the Company’s stockholders approved, the Company’s 2017 Stock Incentive Plan (the “2017 Plan”), which became effective immediately prior to the effectiveness of the registration statement for the IPO. The 2017 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares initially reserved for issuance under the 2017 Plan was the sum of 7,161 shares, plus the number of shares (up to 18,746 shares) equal to the sum of (i) the number of shares remaining available for issuance under the 2003 Plan and 2011 Plan upon the effectiveness of the 2017 Plan and (ii) the number of shares of common stock subject to outstanding awards under the 2003 Plan and 2011 Plan that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right. The number of shares of common stock that may be issued under the 2017 Plan will automatically increase on each January 1, beginning with the fiscal year ending December 31, 2019 and continuing for each fiscal year until, and including, the fiscal year ending December 31, 2027, equal to the least of ( i ) 20,000 shares, (ii) 4 % of the outstanding shares of common stock on such date and (iii) an amount determined by the Company’s board of directors. The shares of common stock underlying any awards that are forfeited, canceled, repurchased or otherwise terminated by the Company under the 2017 Plan will be added back to the shares of common stock available for issuance under the 2017 Plan. The total number of shares authorized for issuance under the 2017 Plan was 20,480 shares as of December 31, 2021 , of which 9,810 shares remained available for future grant. Upon the closing of the IPO on December 19, 2017, the Company filed a restated certificate of incorporation, which authorized the Company to issue 500,000 shares of $0.001 par value common stock. Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the board of directors, if any, subject to the preferential dividend rights of the preferred stock. Through December 31, 2021, except for the special cash dividends declared on November 30, 2014, June 17, 2016, December 21, 2016, May 10, 2017 and November 30, 2017 (see Note 12), no dividends have been declared by the board of directors. As of December 31, 2021, the Company had reserved 10,670 shares of common stock for the exercise of outstanding stock options and the vesting of outstanding RSUs and PSUs under the Company’s 2017 Plan. Stock Repurchase Program On February 21, 2019, the Company announced a stock repurchase program authorizing it to repurchase up to $75,000 of the Company’s common stock. During the years ended December 31, 2021, 2020 and 2019, the Company repurchased 1,671, 1,227 and 495 shares for $8,819, $3,031 and $1,795, respectively, including commissions. As of December 31, 2021, $61,423 remained authorized for repurchases of the Company’s common stock under this stock repurchase program. Stock Option Valuation The Company uses the closing price of its common stock as reported on the Nasdaq Global Select Market on the applicable date of grant to determine the fair value of the shares of common stock underlying stock options. The assumptions used in the Black-Scholes option-pricing model were as follows: Year Ended December 31, 2021 2020 2019 Risk-free interest rate 1.0%–1.3% 0.4%–0.7% 1.6%–2.5% Expected term (in years) 6.1 6.1 6.1-6.2 Expected volatility 37.7%–38.6% 29.3%–31.9% 28.8%–30.6% Expected dividend yield 0.0% 0.0% 0.0% Stock Options A summary of option activity for the year ended December 31, 2021 is as follows: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value (in years) Outstanding at January 1, 2021 7,120 $ 8.01 4.88 $ 9,367 Granted 151 7.54 Exercised (1,006 ) 2.25 Forfeited (346 ) 10.66 Outstanding at December 31, 2021 5,919 $ 8.82 4.36 $ 4,205 Options exercisable at December 31, 2021 5,609 $ 8.88 4.13 $ 4,059 Vested or expected to vest at December 31, 2021 5,900 $ 8.83 4.33 $ 4,196 The weighted-average grant-date fair value of options granted during the years ended December 31, 2021, 2020 and 2019 was $2.88, $1.42 and $2.13 per share, respectively. Cash proceeds received upon the exercise of options were $2,263, $1,195 and $2,687 during the years ended December 31, 2021, 2020 and 2019, respectively. The intrinsic value of stock options exercised during the years ended December 31, 2021, 2020 and 2019 was $5,594, $1,746 and $6,970, respectively. The aggregate intrinsic value is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. Restricted Stock Units A summary of RSU activity for the year ended December 31, 2021 is as follows: Number of Shares Weighted- Average Grant Date Fair Value Aggregate Fair Value Unvested balance at January 1, 2021 4,231 $ 5.43 Granted 1,705 8.18 Vested (1,288 ) 6.12 $ 10,427 Forfeited (339 ) 5.01 Unvested balance at December 31, 2021 4,309 $ 6.34 The Company withheld 791, 150 and 77 shares of common stock in settlement of employee tax withholding obligations due upon the vesting of RSUs during the years ended December 31, 2021, 2020 and 2019, respectively. Performance-Based Restricted Stock Units During the years ended December 31, 2021 and 2020, the Company granted performance-based restricted stock unit “PSUs” to certain employees that vest over a three-year Compensation expense for PSUs is based on the estimated value of the awards on the grant date, and is recognized over the period from the grant date through the expected vest dates of each vesting condition, both of which were estimated based on a Monte Carlo simulation model applying the following key assumptions: Year Ended December 31, 2021 2020 Risk-free interest rate 0.2% 1.2% Volatility 78.6% 70.0% Dividend yield 0.0% 0.0% Cost of equity 12.0% 11.0% A summary of PSU activity for the year ended December 31, 2021 is as follows: Number of Shares Weighted- Average Grant Date Fair Value Aggregate Fair Value Unvested balance at January 1, 2021 737 $ 3.22 Granted 442 7.89 Vested (737 ) 3.22 $ 6,449 Forfeited — — Unvested balance at December 31, 2021 442 $ 7.89 Stock Appreciation Rights On three occasions between 2012 and 2017, the Company granted SARs that allow the holder the right, upon exercise, to receive in cash the amount of the difference between the fair market value of the Company’s common stock at the date of exercise and the price of the underlying common stock at the date of grant of each SAR. The SARs vested over a four-year Stock-Based Compensation Expense The Company classified s tock-based compensation expense related to stock options, RSUs, PSUs and SARs for the years ended December 31, 2021, 2020 and 2019 in the consolidated statements of operations and comprehensive income (loss) as follows: Year Ended December 31, 2021 2020 2019 Cost of revenue $ 137 $ 153 $ 216 Research and development expenses 2,665 2,447 1,569 Selling, general and administrative 12,017 10,555 8,036 $ 14,819 $ 13,155 $ 9,821 The Company recognized s tock-based compensation expense for the years ended December 31, 2021, 2020 and 2019 in the consolidated balance sheets as follows: Year Ended December 31, 2021 2020 2019 Change in fair value of SAR liability $ — $ 229 $ (1,123 ) Recognized as additional paid-in capital 14,819 12,926 10,944 Total stock-based compensation $ 14,819 $ 13,155 $ 9,821 As of December 31, 2021, there was $21,705 of unrecognized compensation cost related to outstanding stock options, RSUs, PSUs and SARs, which is expected to be recognized over a weighted-average period of 2.48 years.

Net Income (Loss) per Share

Net Income (Loss) per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Income (Loss) per Share	14. Net Income (Loss) per Share The Company calculated b asic and diluted net income (loss) per share attributable to common stockholders as follows: Year Ended December 31, 2021 2020 2019 Numerator: Net income (loss) attributable to common stockholders, basic and diluted $ 3,207 $ 24,801 $ (48,206 ) Denominator: Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, basic 85,253 83,465 83,853 Dilutive effect of stock options 1,526 1,050 — Dilutive effect of restricted stock units 2,078 763 — Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, diluted 88,857 85,278 83,853 Net income (loss) per share attributable to common stockholders: Basic $ 0.04 $ 0.30 $ (0.57 ) Diluted $ 0.04 $ 0.29 $ (0.57 ) The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net income (loss) per share attributable to common stockholders for the periods presented because including them would have been anti-dilutive: Year Ended December 31, 2021 2020 2019 Options to purchase common stock 3,411 4,119 4,641 Unvested restricted stock units 712 1,030 1,516 Unvested performance-based stock units — 983 —

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2021
Revenue From Contract With Customer [Abstract]
Revenue from Contracts with Customers	15. Revenue from Contracts with Customers Disaggregation of revenue The Company disaggregates its revenue by product and service in the consolidated statements of operations and comprehensive income (loss). The Company recognizes performance obligations related to product revenue at a point in time, and performance obligations related to service revenue over time. The Company also disaggregates its revenue based on geographic locations of its customers, as determined by the customer’s shipping address, summarized as follows: Year Ended December 31, 2021 2020 2019 North America: United States $ 154,765 $ 127,217 $ 103,451 Canada 66,537 38,960 36,466 Total North America 221,302 166,177 139,917 Latin America 27,841 34,926 24,043 Europe, Middle East and Africa: 30,378 35,933 38,154 Asia-Pacific Australia 89,548 116,661 42,218 Other 32,256 39,549 37,965 Total Asia-Pacific 121,804 156,210 80,183 Total revenue ( 1) $ 401,325 $ 393,246 $ 282,297 (1) Other than the United States, Canada and Australia, no individual countries represented 10% or The Company also disaggregates its revenue based on product line summarized as follows: Year Ended December 31, 2021 2020 2019 Product revenue: Wireless $ 170,233 $ 111,255 $ 58,234 Fixed telco 66,017 96,904 38,734 Cable 117,692 137,924 144,409 Total product revenue 353,942 346,083 241,377 Service revenue Wireless 5,538 7,348 1,701 Fixed telco 5,034 1,924 773 Cable 36,811 37,891 38,446 Total service revenue 47,383 47,163 40,920 Total revenue $ 401,325 $ 393,246 $ 282,297 Costs to Obtain or Fulfill a Contract As of December 31, 2021, 2020 and 2019, the Company had short-term capitalized contract costs of $90, $95 and $585, respectively, which are included in prepaid expenses and other current assets and had long-term capitalized contract costs of $58, $70 and $70, respectively, which are included in other assets in the accompanying consolidated balance sheets. During the years ended December 31, 2021, 2020 and 2019, amortization expense associated with capitalized contract costs was $98, $568 and $695, respectively, Contract Balances Contract liabilities consist of deferred revenue and include payments received in advance of performance under the contract. The Company recognizes such amounts as revenue when the Company satisfies its performance obligations. For the year ended December 31, 2021, the Company recognized $15,402 of revenue which was included in deferred revenue as of December 31, 2020. For the year ended December 31, 2020, the Company recognized The Company receives payments from customers based upon contractual billing terms. The Company records a ccounts receivable when the right to consideration becomes unconditional. Contract assets include amounts related to the Company’s contractual right to consideration for both completed and partially completed performance obligations that may not have been invoiced. As of December 31 , 2021 and 2020 , the Company recorded contract assets of $ and $ 771 , respectively . Transaction price allocated to the remaining performance obligations As of December 31, 2021, the aggregate remaining amount of revenue expected to be recognized related to unsatisfied or partially unsatisfied performance obligations is $21,486, which consists of deferred revenue. The Company expects approximately 67% of this amount to be recognized in the next twelve months with the remaining amounts to be recognized over the next two to five years.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Segment Information	16. Segment Information The Company operates as one operating segment. Operating segments are defined as components of an enterprise for which separate financial information is regularly evaluated by the Company’s chief operating decision maker, or decision-making group, in deciding how to allocate resources and assess performance. The Company has determined that its chief operating decision maker is its President and Chief Executive Officer. The Company’s chief operating decision maker reviews the Company’s financial information on a consolidated basis for purposes of allocating resources and assessing financial performance. Since the Company operates as one operating segment, all required financial segment information can be found in these consolidated financial statements. Please refer to Note 15 for the Company’s revenue by geography for the years ended December 31, 2021, 2020 and 2019. The Company’s property and equipment, net by location was as follows: December 31, 2021 2020 United States $ 17,089 $ 20,988 China 3,118 2,986 Australia 2,027 2,849 Other 1,274 2,057 Total property and equipment, net $ 23,508 $ 28,880

Related Parties

Related Parties	12 Months Ended
	Dec. 31, 2021
Related Party Transactions [Abstract]
Related Parties	17. Related Parties Employment of Rongke Xie Rongke Xie, who serves as General Manager of Guangzhou Casa Communication Technology LTD (“Casa China”), a subsidiary of the Company, is the sister of Lucy Xie, the Company’s Senior Vice President of Operations and a member of the Company’s board of directors. Casa China paid Rongke Xie $224, $187 and $117 in total compensation in the years ended December 31, 2021, 2020 and 2019, respectively, for her services as an employee. To date, the Company has granted to Rongke Xie 116 RSUs which vest in annual installments over a four-year

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	18. Commitments and Contingencies Operating Leases The Company leases manufacturing, warehouse and office space in the United States, China, Hong Kong, Spain and Australia under non-cancelable operating leases that expire through 2027. The Company also has a lease in Ireland that expires in 2026 . Rent expense for the years ended December 31, 2021 , 2020 and 2019 was $ 3,222 , $ and $ , respectively. The Company records r ent expense on a straight-line basis, and, as a result, as of December 31, 2021 and 2020 , the Company had a deferred rent liability of $ 151 and $ 90 , respectively, which is included in accrued expenses and other current liabilities in the accompanying consolidated balance sheets. Future minimum lease payments under non-cancelable operating leases as of December 31, 2021 were as follows: Year Ending December 31, 2022 $ 2,138 2023 2,028 2024 1,116 2025 874 2026 795 Thereafter 511 $ 7,462 Indemnification The Company has, in the ordinary course of business, agreed to defend and indemnify certain customers against third-party claims asserting (i) infringement of certain intellectual property rights, which may include patents, copyrights, trademarks or trade secrets, and (ii) certain other harms caused by the acts or omissions of the Company. As permitted under Delaware law, the Company indemnifies its officers, directors and employees for certain events or occurrences that happen by reason of their relationship with or position held at the Company. As of December 31, 2021 and 2020, the Company had not experienced any material losses related to these indemnification obligations and no material claims were outstanding where a contingent loss was considered to be probable or reasonably estimable. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related liabilities were recorded in its consolidated financial statements. Litigation From time to time, the Company is a party to various litigation matters and subject to claims that arise in the ordinary course of business including, for example, patent infringement lawsuits by non-practicing entities. In addition, third parties may from time to time assert claims against the Company in the form of letters and other communications. The Company is not presently subject to any pending or threatened litigation that it believes, if determined adversely to the Company, individually, or taken together, would reasonably be expected to have a material adverse effect on its business or financial results, except as described below. On May 29, 2019, John Shen filed a putative shareholder class action complaint in the Massachusetts Superior Court of Essex County, John Shen v. Casa Systems, Inc, et al., Civil Action No. 1977CV00787 Mirza R. Baig v. Casa Systems, Inc., Civil Action No. 1977CV00961 , against the same defendants. The two matters were subsequently consolidated and transferred to the Business Litigation Session of the Massachusetts Superior Court, Suffolk County, John Shen v. Casa Systems, Inc, et al., Civil Action No. 19-CV-03203-BLS2 and Mirza R. Baig v. Casa Systems, Inc., Civil Action No. 19-CV-03204-BLS2 . relief. On January 12, 2021, the court granted motions to dismiss filed by the defendants. On February 22, 2021, plaintiffs filed notice of appeal. On August 9, 2019, Donald Hook filed a putative shareholder class action lawsuit in the Supreme Court of the State of New York, County of New York, Donald Hook, et al., v. Casa Systems, Inc. et al., Index No. 654548/2019 On August 13, 2019, Panther Partners, Inc. filed a putative shareholder class action lawsuit in the Supreme Court of the State of New York, New York County, Panther Partners, Inc., et al., v. Jerry Guo et al., Index No 654585/2019 The Company is generally obligated to indemnify our officers, directors, and the IPO and Follow-on Offering underwriters in each of the matters described above. No amounts have been accrued for any of the putative class action lawsuits referenced above as of December 31, 2021, as we do not believe the likelihood of a material loss is probable. Although the ultimate outcome of these matters cannot be predicted with certainty, the resolution of any of these matters could have a material impact on our results of operations in the period in which such matter is resolved.

Employee Benefit Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2021
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plan	19. Employee Benefit Plan The Company has a Section 401(k) defined contribution savings plan for its employees. The plan covers substantially all employees in the United States who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis, subject to certain limitations. Company contributions to the plan may be made at the discretion of the board of directors. Effective January 1, 2014, the Company commenced matching contributions in the amount of 50% of the employee’s contributions of up to 6% of eligible wages. The Company made matching contributions to the plan of $1,615, $1,523 and $1,762 in the years ended December 31, 2021, 2020 and 2019, respectively.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and judgments relied upon by management in preparing these consolidated financial statements include revenue recognition, reserves for excess and obsolete inventory, valuation of inventory and deferred inventory costs, the expensing and capitalization of software-related research and development costs, amortization and depreciation periods, the recoverability of net deferred tax assets, valuations of uncertain tax positions, warranty allowances, the valuation of equity instruments and stock-based compensation expense. Although the Company regularly reassesses the assumptions underlying these estimates, actual results could differ materially from these estimates. Changes in estimates are recorded in the period in which they become known. The Company bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances existing at the time such estimates are made . The COVID-19 pandemic presents various risks to the Company, not all of which the Company is able to fully evaluate or even to foresee at the current time, and which could have a material effect upon the estimates and judgments relied upon by management in preparing these consolidated financial statements. While the Company remains fully operational, during the year ended December 31, 2021, the effects of the COVID-19 pandemic on the global supply chain had a significant adverse effect on the Company’s financial results. In particular, certain of the Company’s products utilize components, whose availability was significantly exceeded by global demand. As a result, throughout 2021, the Company began to see shortages of supply that resulted in the Company’s inability to fulfill certain customer orders within normal lead times. This adversely impacted the Company’s revenue and operating results for year ended December 31, 2021. Additionally, shipping bottlenecks and delays negatively affected the Company’s ability to timely fulfill customer orders, thereby delaying its ability to consummate sales and recognize revenue. The Company also experienced, in some cases, significant increases in shipping costs. While the Company continues to work with its supply chain, contract manufacturers, logistics partners and customers to minimize the extent of such impacts, the Company expects the effects of global supply chain issues to continue and cannot predict when such effects will subside. This may prevent the Company from being able to fulfill its customers’ orders in a timely manner or at all, which could lead to one or more of its customers cancelling their orders. At this time the Company is neither able to estimate the extent of these impacts nor predict whether its efforts to minimize or contain them will be successful. The Company intends to continue to monitor its business very closely for any effects of COVID-19 for as long as necessary.
Subsequent Event Considerations	Subsequent Event Considerations The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated as required. The Company has evaluated all subsequent events and determined that there are no material recognized or unrecognized subsequent events requiring disclosure in these consolidated financial statements.
Cash and Cash Equivalents, Restricted Cash	Cash, Cash Equivalents and Restricted Cash Cash and cash equivalents include all highly liquid investments maturing within three months from the date of purchase. As of December 31, 2021 and 2020, the Company’s cash and cash equivalents consisted of investments in money market mutual funds. Restricted cash as of December 31, 2021 and 2020 consisted of a certificate of deposit of $1,001 and $1,006, respectively, pledged as collateral for a stand-by letter of credit required to support a contractual obligation. Restricted cash as of also included cash of $2,100 pledged as collateral in connection with two letters of credit to support contractual obligations, as further discussed in Note 11, Debt. The following table is a reconciliation of cash, cash equivalents and restricted cash included in the accompanying consolidated balance sheets that sum to the total cash, cash equivalents and restricted cash included in the accompanying consolidated statements of cash flows. December 31, 2021 December 31, 2020 Cash and cash equivalents $ 154,703 $ 157,455 Restricted cash included in other assets 3,101 1,006 $ 157,804 $ 158,461
Accounts Receivable	Accounts Receivable Accounts receivable are presented net of a provision for doubtful accounts, which is an estimate of amounts that may not be collectible. Accounts receivable for customer contracts with customary payment terms, which are one year or less, are recorded at invoiced amounts and do not bear interest. The Company may, in limited circumstances, grant payment terms longer than one year. Payments due beyond 12 months from the balance sheet date are recorded as non-current assets. The Company generally does not require collateral, but the Company may, in certain instances based on its credit assessment, require full or partial prepayment prior to shipment . Accounts receivable as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Current portion of accounts receivable, net: Accounts receivable, net $ 85,689 $ 93,480 Accounts receivable, extended payment terms 85 644 85,774 94,124 Accounts receivable, net of current portion: Accounts receivable, extended payment terms 115 143 $ 85,889 $ 94,267 The Company performs ongoing credit evaluations of its customers and, if necessary, provides a provision for doubtful accounts and expected losses. When assessing and recording its provision for doubtful accounts, the Company evaluates the age of its accounts receivable, current economic trends, creditworthiness of the customer, customer payment history, and other specific customer and transaction information. The Company writes off accounts receivable against the provision when it determines a balance is uncollectible and no longer actively pursues collection of the receivable. Adjustments to the provision for doubtful accounts are recorded as selling, general and administrative expenses in the consolidated statements of operations and comprehensive income (loss). A summary of changes in the provision for doubtful accounts for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Provision for doubtful accounts at beginning of year $ 58 $ 20 $ 410 Provisions and recoveries 59 38 560 Write-offs — — (950 ) Provision for doubtful accounts at end of year $ 117 $ 58 $ 20 As of December 31, 2021 and 2020, the Company concluded that all amounts due under extended payment terms were collectible and no reserve for credit losses was recorded. During the years ended December 31, 2021, 2020 and 2019, the Company did not provide a reserve for credit losses and did not write off any uncollectible receivables due under extended payment terms.
Inventories	Inventories The Company values inventories at the lower of cost or market value. The Company computes cost using the first-in first-out convention. Inventories are composed of hardware and related component parts of finished goods. The Company establishes provisions for excess and obsolete inventories after evaluating historical sales, future demand, market conditions, expected product life cycles, and current inventory levels to reduce such inventories to their estimated net realizable value. The Company makes such provisions in the normal course of business and charges them to cost of revenue in its consolidated statements of operations and comprehensive income (loss). The Company includes deferred inventory costs within inventory in its consolidated balance sheets. Deferred inventory costs represent the cost of products that have been delivered to the customer for which revenue associated with the arrangement has been deferred as a result of not meeting all of the required revenue recognition criteria, such as receipt of customer acceptance. The Company recognizes deferred inventory costs as cost of revenue in its consolidated statements of operations and comprehensive income (loss) when the related revenue is recognized.
Property and Equipment	Property and Equipment The Company states property and equipment at historical cost less accumulated depreciation. The Company computes depreciation using the straight-line method over the estimated useful lives of the assets. The Company records leasehold improvements at cost with any reimbursement from the landlord being accounted for as deferred rent, which is amortized using the straight-line method over the lease term. The Company also includes costs for trial systems held and used by its customers pursuant to evaluation agreements within property and equipment. The Company depreciates trial systems held and used by its customers over the estimated useful life of such assets, which is two years. Whenever a trial system is sold to a customer and the selling price is recorded as revenue, the Company removes the related net book value of the trial system sold from property and equipment and records it as a cost of revenue. The Company expenses maintenance and repairs expenditures as incurred. Estimated useful lives of the respective property and equipment assets are as follows: Estimated Useful Life Computers and purchased software 3 – 4 years Leasehold improvements Shorter of lease term or 7 years Furniture and fixtures 6 – 8 years Machinery and equipment 3 – 10 years Building 40 years Building improvements 5 – 40 years Trial systems at customers’ sites 2 years Upon retirement or sale, the Company removes the cost of assets disposed of and the related accumulated depreciation from the accounts and any resulting gain or loss is included in income (loss) from operations.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates its long-lived assets, which consist primarily of property and equipment and intangible assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. The Company measures recoverability of assets to be held and used by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the Company measures the impairment to be recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset, less the cost to sell. No events or changes in circumstances existed to require an impairment assessment during the years ended December 31, 2021, 2020 and 2019.
Concentration of Risks	Concentration of Risks Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents and accounts receivable. Cash and cash equivalents consist of demand deposits, savings accounts, money market mutual funds, and certificates of deposit with financial institutions, which may exceed Federal Deposit Insurance Corporation limits. The Company has not experienced any losses related to its cash and cash equivalents and does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company grants credit to customers in the ordinary course of business. Credit evaluations are performed on an ongoing basis to reduce credit risk, and no collateral is required from our customers. An allowance for uncollectible accounts is provided for those accounts receivable considered to be uncollectible based upon historical experience and credit evaluation. Due to these factors, no additional losses beyond the amounts provided for collection losses is believed by management to be probable in the Company’s accounts receivable. Significant customers are those that represent 10% or more of revenue or accounts receivable and are set forth in the following tables: Revenue Accounts Receivable, Net Year Ended December 31, December 31, 2021 2020 2019 2021 2020 Customer A 22 % 11 % * 21 % 14 % Customer B * * * 19 % * Customer C * * * 10 % * Customer D * 20 % 12 % * * Customer E * * 14 % * * * Less than 10% of total Certain of the components and subassemblies included in the Company’s products are obtained and manufactured from a single source or a limited group of suppliers. Although the Company seeks to reduce dependence on those single or limited source suppliers and manufacturers, the partial or complete loss of certain of these sources could have a material adverse effect on the Company’s operating results, financial condition and cash flows and damage its customer relationships.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill represents the excess purchase price over the estimated fair value of net assets acquired as of the acquisition date. Goodwill has been recorded in connection with the acquisition of NetComm on July 1, 2019 (refer to Note 3). The Company tests goodwill for impairment on an annual basis and between annual tests when impairment indicators are identified, and goodwill is written down when impaired. The Company performs its annual goodwill impairment test during its fourth quarter. For its annual goodwill impairment test, the Company operates under one reporting unit and the fair value of its reporting unit has been determined based on the Company’s enterprise value. As part of the annual goodwill impairment test, the Company has the option to perform a qualitative assessment to determine whether further impairment testing is necessary. Examples of events and circumstances that might indicate that the reporting unit’s fair value is less than its carrying amount include macro-economic conditions such as deterioration in the entity’s operating environment or industry or market considerations; entity-specific events such as increasing costs, declining financial performance, or loss of key personnel; or other events such as a sustained decrease in the stock price on either an absolute basis or relative to peers. If, as a result of its qualitative assessment, it is more likely than not (i.e., greater than 50% chance) that the fair value of the Company’s reporting unit is less than its carrying amount, the quantitative impairment test will be required. Otherwise, no further testing will be required. The Company completed its qualitative assessment and concluded that as of December 31, 2021 and 2020, it is not more likely than not that the fair value of the Company’s reporting unit is less than its carrying amount. The Company amortizes its acquired intangible assets subject to amortization using the straight-line method over their estimated useful lives, ranging from 3 to 10 years. Purchased software licenses are classified as intangible assets and are amortized using the straight-line method over their estimated useful lives, typically ranging from 3 to 4 years. The Company evaluates the recoverability of intangible assets periodically by taking into account events or circumstances that may warrant revised estimates of useful lives or that indicate the asset may be impaired. The Company considered potential impairment indicators of acquired intangible assets at December 31, 2021 and 2020 and noted no indicators of impairment.
Product Warranties	Product Warranties Substantially all of the Company’s products are covered by a warranty for software and hardware for periods ranging from 90 days to one year. In addition, in conjunction with customers’ renewals of maintenance and support contracts, the Company offers an extended warranty for periods typically of one to three years for agreed-upon fees. In the event of a failure of a hardware product or software covered by these warranties, the Company must repair or replace the software or hardware or, if those remedies are insufficient, and at the discretion of the Company, provide a refund. The Company’s warranty reserve, which is included in accrued expenses and other current liabilities in the consolidated balance sheets, reflects estimated material, labor and other costs related to potential or actual software and hardware warranty claims for which the Company expects to incur an obligation. The Company’s estimates of anticipated rates of warranty claims and the costs associated therewith are primarily based on historical information and future forecasts. The Company periodically assesses the adequacy of the warranty reserve and adjusts the amount as necessary. If the historical data used to calculate the adequacy of the warranty reserve are not indicative of future requirements, additional or reduced warranty reserves may be required. A summary of changes in the amount reserved for warranty costs for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Warranty reserve at beginning of year $ 2,354 $ 2,448 $ 926 Provisions 2,339 2,745 3,603 Acquired warranty reserve — — 1,867 Charges (2,301 ) (2,839 ) (3,948 ) Warranty reserve at end of year $ 2,392 $ 2,354 $ 2,448
Revenue Recognition	Revenue Recognition Effective January 1, 2019, the Company adopted ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”) using the modified retrospective transition method. This method was applied to contracts that were not complete as of the date of initial application. The following is a summary of new and/or revised significant accounting policies affected by the Company’s adoption of ASC 606, which relate primarily to revenue and cost recognition. The Company generates revenue from sales of its products, along with associated maintenance, support and extended hardware warranty services, and to a lesser extent, from sales of professional services. Maintenance and support services include telephone support, bug fixes and unspecified software upgrades and updates provided on a when-and-if-available basis and/or extended hardware warranty. In its consolidated statements of operations and comprehensive income (loss), the Company classifies revenue from sales of cable, wireless and fixed telco products as product revenue, and revenue from maintenance and support and professional services as service revenue. In accordance with ASC 606, the Company recognizes revenue when a customer obtains control of promised products or services. The amount of revenue recognized reflects the consideration that the Company expects to be entitled to receive in exchange for these products or services. To achieve the core principle of this standard, the Company applies the following five steps: 1) Identify the contract with a customer 2) Identify the performance obligations in the contract 3) Determine the transaction price 4) Allocate the transaction price to performance obligations in the contract 5) Recognize revenue when or as the Company satisfies a performance obligation Performance Obligations The majority of the Company’s contracts with customers contain multiple performance obligations including products and maintenance services, and on a limited basis, professional services. For these contracts, the Company accounts for individual performance obligations separately if they are considered distinct. The Company’s cable, wireless and fixed telco products, maintenance services and professional services are considered distinct performance obligations. When multiple performance obligations exist in a customer contract, the Company allocates the transaction price to the separate performance obligations on a relative SSP basis. The Company determines SSP using its judgment and based on the best evidence available, which may include the selling price of products when sold on a standalone basis to similar customers in similar circumstances, or in the absence of standalone sales, taking into consideration the Company’s historical pricing practices by customer type, selling method (i.e., resellers or direct), and geographic-specific market factors. Product revenue Some of the Company’s cable, wireless and fixed telco products have both software and non-software (i.e., hardware) components that function together to deliver the products’ essential functionality. In these instances, the Company’s hardware cannot be used apart from the embedded software and is considered one distinct performance obligation. The Company recognizes revenue for both new and existing customers at a point in time when control of the products is transferred to the customer, which is typically when title and risk of loss have transferred and the right to payment is enforceable. The Company also earns revenue from the sale of perpetual software licenses and/or software-enabled capacity expansions. Revenue on perpetual software licenses and software-enabled capacity expansions for existing customers are also distinct performance obligations as they are separately identifiable and provide additional bandwidth capacity on hardware products already purchased by the customer. The Company recognizes revenue on perpetual software licenses and software-enabled capacity expansions when control is transferred, which is typically as the software entitlements are made available to the customer. When customer contracts require acceptance of product and services, the Company considers the nature of the acceptance provisions to determine if they are substantive or considered perfunctory to determine if these acceptance provisions impact the timing of revenue recognition. When acceptance provisions are considered substantive, the Company will defer revenue on all performance obligations in the contract subject to acceptance until acceptance has been received. The Company does not defer revenue when acceptance provisions are deemed perfunctory. Maintenance and Support Services and Professional Services Revenue Other than for certain of our CPE products, the Company generally sells its products with maintenance and support services, a distinct performance obligation that includes the stand-ready obligation to provide telephone support, bug fixes and unspecified software upgrades and updates provided on a when-and-if-available basis and/or extended hardware warranty. After the initial sale, customers may purchase annual renewals of support contracts. The Company’s telephone support and unspecified upgrades and updates are delivered over time and the Company therefore recognizes revenue ratably over the contract term, which is typically one year, but can be as long as five years. The Company also generates revenue from sales of professional services, such as installation, configuration and training. Professional services are a distinct performance obligation since the Company’s products are functional without these services and can generally be performed by the customer or a third party. The Company generally recognizes fee-based professional services delivered at a point in time as the professional services are completed and upon receipt of acceptance if applicable. The sale of the Company’s products generally includes a 90-day warranty on the software and a one-year Resellers and Sales Agents The Company markets and sells its products through its direct global sales force, supported by sales agents, and through resellers. The Company’s resellers receive an order from an end customer prior to placing an order with the Company, and the Company confirms the identification of or is aware of the end customer prior to accepting such order. The Company invoices the reseller an amount that reflects a reseller discount and records revenue based on the amount of the discounted transaction value. Aside from wireless and fixed telco hardware products, the Company’s resellers do not stock inventory received from the Company. When the Company transacts with a reseller, the contract is with the reseller and not with the end customer. Whether the Company transacts business with and receives the order directly from the reseller or a customer, its revenue recognition policy and resulting pattern of revenue recognition for the order are the same. The Company has assessed whether it is principal (i.e., reports revenue on a gross basis) or agent (i.e., reports revenues on a net basis) by evaluating whether it has control of the good or service before it is transferred to the reseller. As the Company controls the promised good or service before transferring it to the reseller, it acts as the principal in the transaction. Accordingly, the Company reports revenues on a gross basis. The Company also uses sales agents that assist in the sales process with certain customers, primarily located in the Latin America and Asia-Pacific regions. Sales agents are not resellers. If a sales agent is engaged in the sales process, the Company receives the order directly from the end customer and sells the products and services directly to the end customer, and the Company pays a commission to the sales agent, calculated as a percentage of the related transaction value. Accounting considerations related to sales agent commissions are discussed in the “Costs to Obtain or Fulfill a Contract” section below. Costs to Obtain or Fulfill a Contract The Company capitalizes commission expenses paid to internal sales personnel and sales agent commissions that are incremental to obtaining customer contracts, for which the related revenue is recognized over a future period greater than 12 months. These costs are incurred on initial sales of product, professional services and maintenance and support contract renewals. The Company defers these costs and amortizes them over the period of benefit, which is generally considered to be the contract term. The Company has elected to use the practical expedient, allowing the Company to recognize the incremental costs of obtaining a contract as an expense when incurred if the amortization period of the asset that the entity otherwise would have recognized is one year or less. Commissions paid relating to maintenance and support contract renewals of twelve months or less are expensed as incurred as commissions paid on renewals are commensurate with commissions paid on initial sales transactions. Costs to obtain a contract for professional services contracts are expensed as incurred in accordance with the practical expedient as the contractual period of our professional services contracts are one year or less. The Company periodically reviews the carrying amount of capitalized contract costs to determine whether events or changes in circumstances have occurred that could impact the period of benefit. Deferred Revenue The Company recognizes amounts billed in excess of revenue recognized as deferred revenue. Deferred revenue includes customer deposits, amounts billed for maintenance and support services contracts in advance of services being performed, amounts for trade-in right liabilities and amounts related to contracts that have been deferred as a result of not meeting the required revenue recognition criteria as of the end of the reporting period. The Company reports deferred revenue expected to be recognized as revenue more than one year subsequent to the balance sheet date within long-term liabilities in the consolidated balance sheets. The Company defers recognition of direct costs, such as cost of goods and services, until recognition of the related revenue. The Company classifies such costs as current assets if the related deferred revenue is classified as current and as non-current assets if the related deferred revenue is classified as non-current. Other Revenue Recognition Policies The Company’s customary payment terms are generally 90 days or less. The Company has elected to apply the practical expedient that allows an entity to not adjust the promised amount of consideration in customer contracts for the effect of a significant financing component when the period between the transfer of product and services and payment of the related consideration is less than one year. If the Company provides extended payment terms that represent a significant financing component, the Company adjusts the amount of promised consideration for the time value of money using an appropriate discount rate and recognizes interest income separate from the revenue recognized on contracts with customers. During the years ended December 31, 2021, 2020 and 2019, the Company recorded $20, $64 and $160, respectively, in interest income in its consolidated statements of operations and comprehensive income (loss) related to arrangements with customers that were determined to have a significant financing component. In limited instances, the Company has offered future rebates to customers based on a fixed or variable percentage of actual sales volumes over specified periods. The future rebates earned based on the customer’s purchasing from the Company in one period may be used as credits to be applied by them against accounts receivable due to the Company in later periods. The Company accounts for these future rebates as variable consideration and reduces the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will occur when the variable consideration is resolved. The Company estimates the reduction of the transaction price based on historical activity and other relevant factors and recognizes it when the Company recognizes revenue for the transfer of goods and services to the customer on which the future rebate was earned. Other forms of contingent revenue or variable consideration are infrequent. The Company excludes any taxes assessed by a governmental authority that are directly imposed on a revenue-producing transaction (e.g., sales, use and value added taxes) from its transaction price. The Company records b illings to customers for reimbursement of out-of-pocket expenses, including travel, lodging and meals, as revenue, and the associated costs incurred by the Company as cost of revenue. Revenue related to the reimbursement of out-of-pocket costs are accounted for as variable consideration . The Company accounts for any shipping and handling activities as a fulfilment cost rather than an additional promised service. The Company records shipping and handling billed to customers as an offset to cost of revenue.
Stock-Based Compensation	Stock-Based Compensation The Company measures stock options and other stock-based awards granted to employees and directors based on the fair value on the date of grant and recognizes compensation expense of those awards, net of estimated forfeitures, over the requisite service period, which is generally the vesting period of the respective award. Generally, the Company issues stock options with only service-based vesting conditions and records the expense for these awards using the straight-line method. The Company classifies stock-based compensation expense in its consolidated statements of operations and comprehensive income (loss) in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. The Company recognizes compensation expense for only the portion of awards that are expected to vest. In developing a forfeiture rate estimate, the Company has considered its historical experience to estimate pre-vesting forfeitures for service-based awards. The impact of a forfeiture rate adjustment will be recognized in full in the period of adjustment, and if the actual forfeiture rate is materially different from the Company’s estimate, the Company may be required to record adjustments to stock-based compensation expense in future periods. The Company estimates the fair value of each stock option and stock appreciation right, or SAR, grant on the date of grant using the Black-Scholes option pricing model. The Company was a private company until December 14, 2017 and lacked sufficient company-specific historical and implied volatility information for its stock. Therefore, for all options granted in 2020 or before, the Company estimated its expected stock volatility based on the historical volatility of publicly traded peer companies. Beginning with options granted in 2021, the Company estimates its expected stock volatility using a weighted-average calculation based on the historical volatility of the Company and publicly traded peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company does not have a history of declaring or paying cash dividends, except for the special cash dividends declared in November 2014, June 2016, December 2016, May 2017 and November 2017 and in those circumstances the board of directors approved cash dividends to be paid to holders of the Company’s stock options, stock appreciation rights (“SARs”) and restricted stock units (“RSUs”) upon vesting as an equitable adjustment to the holders of such instruments. The Company has granted SARs to certain employees, which require the Company to pay in cash, upon exercise, an amount equal to the product of the excess of the per share fair market value of the Company’s common stock on the date of exercise over the exercise price, multiplied by the number of shares of common stock with respect to which the SAR is exercised. Because these awards may require the Company to settle the awards in cash, the Company accounts for them as a liability in the Company’s consolidated balance sheets. The Company recognizes the liability related to these awards, as well as related compensation expense, over the period during which services are rendered until completed. All SAR awards became fully vested on January 1, 2020. The Company will continue to remeasure the fair market value of the liability until the award is either exercised or canceled, with changes in the fair value of the liability recorded in the consolidated statements of operations and comprehensive income (loss).
Research and Development Costs	Research and Development Costs The Company expenses research and development costs as incurred. The Company expenses costs incurred to develop software to be licensed to customers prior to the establishment of technological feasibility of the software and capitalizes them thereafter until commercial release of the software. The Company has not historically capitalized software development costs as the establishment of technological feasibility typically occurs shortly before the commercial release of its software, which is embedded in its products. As such, the Company expenses all software development costs related to software to be licensed to customers as incurred and includes such amounts within research and development expense in the accompanying consolidated statements of operations and comprehensive income (loss).
Advertising Costs	Advertising Costs The Company expenses advertising costs as incurred and includes them in selling, general and administrative expense in the accompanying consolidated statements of operations and comprehensive income (loss). Advertising expenses were not significant for any periods presented.
Foreign Currency Translation	Foreign Currency Translation For the Company’s subsidiaries in Ireland and Australia, the U.S. dollar is the functional currency. For each of the Company’s other foreign subsidiaries, the functional currency is its local currency. Assets and liabilities of these foreign subsidiaries are translated into U.S. dollars using period-end exchange rates, and revenues and expenses are translated into U.S. dollars using average exchange rates in effect during each period. The Company includes the effects of these foreign currency translation adjustments in accumulated other comprehensive income (loss), a separate component of stockholders’ equity. The Company includes foreign currency transaction (losses) gains in its consolidated statements of operations and comprehensive income (loss) as a component of other income (expense). They totaled $(2,113), $452 and $298 for the years ended December 31, 2021, 2020 and 2019, respectively.
Fair Value Measurements	Fair Value Measurements The Company carries certain assets and liabilities at fair value under GAAP. Fair value is defined as the price that would be received for an asset or the exit price that would be paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: Level 1— Quoted prices in active markets for identical assets and liabilities. Level 2— Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities at the measurement date; quoted prices in markets that are not active for identical or similar assets and liabilities; or other inputs that are observable or can be corroborated by observable market data. Level 3— Unobservable inputs that involve management judgment and are supported by little or no market activity, including pricing models, discounted cash flow methodologies and similar techniques. The categorization of a financial instrument within the valuation hierarchy is based on the lowest level of input that is significant to the fair value measurement. The Company carries cash equivalents, marketable securities, foreign currency forward contracts and SARs at fair value, determined according to the fair value hierarchy described above (see Note 8). The fair values of cash equivalents, accounts receivable, accounts payable and accrued expenses and other current liabilities approximate their fair values due to the short-term nature of these assets and liabilities, with the exception of amounts recorded by the Company as “accounts receivable, non-current,” which represent amounts billed to customers for which payment has not yet become due and for which an offsetting amount of deferred revenue has been recorded. The carrying values of the Company’s debt obligations (see Note 11) as of December 31, 2021 and 2020 approximated their fair values because the debt bears interest at rates the Company would be required to pay on the issuance of debt with similar terms, based on an analysis of recent market conditions and other Company-specific factors.
Income Taxes	Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial statement and tax basis of assets and liabilities, as measured by enacted tax rates anticipated to be in effect when these differences reverse. This method also requires the recognition of future tax benefits to the extent that realization of such benefits is more likely than not. Deferred tax expense or benefit is the result of changes in the deferred tax assets and liabilities. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. The Company evaluates the potential for recovery of deferred tax assets by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. As of December 31, 2021, the Company determined that it is more like ly than not that its net U.S. deferred tax assets will not be realized, and thus maintains a valuation allowance of $ against its net U.S. deferred tax assets that are not expected to be realized, a n increase of $ during the year ended December 31, 20 2 1 . Additionally, as of December 31, 2021, the Company determined that it is more likely than not that a portion of its net foreign deferred tax assets will not be realized, and thus recognized a valuation allowance of $ against its net foreign deferred tax assets that are not expected to be realized, an increase of $ during the year ended December 31, 2021. The Company records a liability for potential payments of taxes to various tax authorities related to uncertain tax positions and other tax matters. The Company bases the recorded liability on its determination of whether and how much of a tax benefit taken by the Company in its tax filings or positions is “more likely than not” to be realized. The amount of the benefit that may be recognized in the financial statements is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. To the extent that the assessment of such tax positions changes, the Company records the change in estimate in the period in which the determination is made. The Company establishes a liability, which is included in accrued income taxes in the consolidated balance sheets, for tax-related uncertainties based on estimates of whether, and the extent to which, additional taxes will be due. The Company establishes these liabilities when the Company believes that certain positions might be challenged despite its belief that the tax return positions are fully supportable. The Company adjusts the recorded liability in light of changing facts and circumstances. The (benefit from) provision for income taxes includes the impact of the recorded liability and changes thereto. The Company recognizes interest and penalties related to uncertain tax positions within other income (expense) in the accompanying consolidated statements of operations and comprehensive income (loss). The Company records accrued interest and penalties in accrued income taxes in the consolidated balance sheets. For taxable years beginning after January 1, 2018, taxpayers are subjected to the global intangible low-taxed income (“GILTI”) provisions. The GILTI provisions require the Company to currently recognize in U.S. taxable income a deemed dividend inclusion of foreign subsidiary earnings in excess of an allowable return on the foreign subsidiary’s tangible assets. The ability to benefit from a deduction and foreign tax credits against a portion of the GILTI income may be limited under the GILTI rules as a result of the utilization of net operating losses, foreign sourced income, and other potential limitations within the foreign tax credit calculation. During the years ended December 31, 2021, 2020 and 2019 the Company recorded income tax charges of $2,630, $3,483 and $942, respectively, related to GILTI. The Company has made an accounting policy election, as allowed by the SEC and FASB, to recognize the impacts of GILTI within the period incurred. Therefore, no U.S. deferred taxes are provided on GILTI inclusions of future foreign subsidiary earnings.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) includes net income (loss) as well as other changes in stockholders’ equity (deficit) that result from transactions and economic events other than those with stockholders. Comprehensive income (loss) for the periods presented consists of net income (loss) and the change in the cumulative foreign currency translation adjustment.
Net Income (Loss) per Share	Net Income (Loss) per Share Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period. Diluted net income (loss) attributable to common stockholders is computed by adjusting net income (loss) attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net income (loss) per share attributable to common stockholders is computed by dividing the diluted net income (loss) attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period, including potential dilutive common shares. For purpose of this calculation, outstanding stock-based awards are considered potential dilutive common shares.
Impact of Recently Adopted and Issued Accounting Standards	Impact of Recently Adopted Accounting Standards In August 2020, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Codification Update 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity as of July 1, 2021, and the adoption did not have a material impact on the Company’s consolidated financial statements and the accompanying notes thereto. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740) Impact of Recently Issued Accounting Standards In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842): Amendments to FASB Accounting Standards Codification In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments Financial Instruments – Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) , and as such ASU 2016-13 will become effective for private companies, and emerging growth companies that choose to take advantage of the extended transition periods, for fiscal years beginning after December 15, 2022, including interim periods within those fiscal periods, and must be applied using a modified retrospective approach. The Company is currently evaluating the impact ASU 2016-13 will have on its consolidated financial statements In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Reconciliation of Cash, Cash Equivalents and Restricted Cash in Accompanying Condensed Consolidated Balance Sheets	The following table is a reconciliation of cash, cash equivalents and restricted cash included in the accompanying consolidated balance sheets that sum to the total cash, cash equivalents and restricted cash included in the accompanying consolidated statements of cash flows. December 31, 2021 December 31, 2020 Cash and cash equivalents $ 154,703 $ 157,455 Restricted cash included in other assets 3,101 1,006 $ 157,804 $ 158,461
Schedule of Accounts Receivable	Accounts receivable as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Current portion of accounts receivable, net: Accounts receivable, net $ 85,689 $ 93,480 Accounts receivable, extended payment terms 85 644 85,774 94,124 Accounts receivable, net of current portion: Accounts receivable, extended payment terms 115 143 $ 85,889 $ 94,267
Summary of Changes in Provision for Doubtful Accounts	A summary of changes in the provision for doubtful accounts for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Provision for doubtful accounts at beginning of year $ 58 $ 20 $ 410 Provisions and recoveries 59 38 560 Write-offs — — (950 ) Provision for doubtful accounts at end of year $ 117 $ 58 $ 20
Schedule of Estimated Useful Lives of Property and Equipment Assets	Estimated useful lives of the respective property and equipment assets are as follows: Estimated Useful Life Computers and purchased software 3 – 4 years Leasehold improvements Shorter of lease term or 7 years Furniture and fixtures 6 – 8 years Machinery and equipment 3 – 10 years Building 40 years Building improvements 5 – 40 years Trial systems at customers’ sites 2 years
Schedule of Significant Customers Represent 10% or More of Revenue or Accounts Receivable	Significant customers are those that represent 10% or more of revenue or accounts receivable and are set forth in the following tables: Revenue Accounts Receivable, Net Year Ended December 31, December 31, 2021 2020 2019 2021 2020 Customer A 22 % 11 % * 21 % 14 % Customer B * * * 19 % * Customer C * * * 10 % * Customer D * 20 % 12 % * * Customer E * * 14 % * * * Less than 10% of total
Summary of Changes in Amount Reserved for Warranty Costs	A summary of changes in the amount reserved for warranty costs for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Warranty reserve at beginning of year $ 2,354 $ 2,448 $ 926 Provisions 2,339 2,745 3,603 Acquired warranty reserve — — 1,867 Charges (2,301 ) (2,839 ) (3,948 ) Warranty reserve at end of year $ 2,392 $ 2,354 $ 2,448

Goodwill and Intangibles (Table

Goodwill and Intangibles (Tables)	12 Months Ended
	Dec. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets Net	Intangible assets, net consisted of intangible assets resulting from the acquisition of NetComm and purchased software to be used in our products. Intangible assets, net consisted of the following at December 31, 2021 and 2020, respectively: As of December 31, 2021 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Developed technology 25,000 (8,930 ) 16,070 Customer relationships 18,000 (4,500 ) 13,500 Trade name 1,000 (830 ) 170 Purchased Software 1,832 (428 ) 1,404 Totals as of December 31, 2021 $ 45,832 $ (14,688 ) $ 31,144 As of December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Developed technology 25,000 (5,358 ) 19,642 Customer relationships 18,000 (2,700 ) 15,300 Trade name 1,000 (498 ) 502 Purchased Software 432 (32 ) 400 Totals as of December 31, 2020 $ 44,432 $ (8,588 ) $ 35,844
Schedule of Amortization Expense on Existing Intangible Assets	As of December 31, 2021, amortization expense on existing intangible assets for the next five years and beyond is summarized as follows: Year Ending December 31, 2022 $ 5,963 2023 5,764 2024 5,660 2025 5,651 2026 3,606 Thereafter 4,500 $ 31,144
Summary of Amortization Expense	A Year Ended December 31, 2021 2020 Product cost of revenue $ 3,572 $ 3,571 Research and development 396 32 Selling, general and administrative 2,132 2,133 Totals $ 6,100 $ 5,736
Schedule of Carrying Value of Goodwill	The Company’s goodwill is the result of its acquisition of NetComm on July 1, 2019 and represents the excess of purchase price over the estimated fair value of net assets acquired. The changes in the carrying value of goodwill are as follows: Carrying Value of Goodwill Balance at December 31, 2019 $ 50,347 Adjustment recorded to preliminary purchase price allocation (170 ) Balance at December 31, 2020 $ 50,177

Inventory (Tables)

Inventory (Tables)	12 Months Ended
	Dec. 31, 2021
Inventory Disclosure [Abstract]
Schedule of Inventory	Inventory as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Raw materials $ 53,934 $ 50,904 Work in process — 19 Finished goods: Manufactured finished goods 29,597 49,764 Deferred inventory costs 1,297 517 $ 84,828 $ 101,204

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2021
Property Plant And Equipment [Abstract]
Summary of Components of Property and Equipment	Property and equipment as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Computers and purchased software $ 25,775 $ 24,865 Leasehold improvements 4,198 4,148 Furniture and fixtures 2,672 2,644 Machinery and equipment 37,325 36,701 Land 3,091 3,091 Building 4,765 4,765 Building improvements 7,291 7,244 Trial systems at customers’ sites 3,848 5,300 88,965 88,758 Less: Accumulated depreciation and amortization (65,457 ) (59,878 ) $ 23,508 $ 28,880

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Accrued compensation and related taxes $ 21,751 $ 22,785 Accrued warranty (see Note 2) 2,392 2,354 Inventory-related accruals 8,391 855 Other accrued expenses 8,848 13,799 $ 41,382 $ 39,793

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Assets and Liabilities	The following tables present information about the fair value of the Company’s financial assets and liabilities as of December 31, 2021 and 2020 and indicate the level of the fair value hierarchy utilized to determine such fair values: Fair Value Measurements as of December 31, 2021 Using: Level 1 Level 2 Level 3 Total Assets: Certificates of deposit—restricted cash $ — $ 1,001 $ — $ 1,001 Money market mutual funds 93,792 — — 93,792 Forward currency forward contract — 5 — 5 $ 93,792 $ 1,006 $ — $ 94,798 Liabilities: SARs $ — $ — $ 358 $ 358 $ — $ — $ 358 $ 358 Fair Value Measurements as of December 31, 2020 Using: Level 1 Level 2 Level 3 Total Assets: Certificates of deposit—restricted cash — 1,006 — 1,006 Money market mutual funds 114,404 — — 114,404 $ 114,404 $ 1,006 $ — $ 115,410 Liabilities: SARs $ — $ — $ 493 $ 493 $ — $ — $ 493 $ 493
Summary of Changes in Fair Values of SARs Liability	The following table provides a summary of changes in the fair values of the Company’s SARs liability, for which fair value is determined by Level 3 inputs: Year Ended December 31, 2021 2020 2019 Fair value at beginning of the year $ 493 $ 264 $ 1,387 Change in fair value — 229 (1,123 ) Exercises (135 ) — — Fair value at end of year $ 358 $ 493 $ 264
Summary of Company's Cash and Cash Equivalents	The Company’s cash, cash equivalents and restricted cash as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Cash $ 60,911 $ 43,051 Cash equivalents and restricted cash: Restricted cash 3,101 1,006 Money market mutual funds 93,792 114,404 Total cash equivalents and restricted cash 96,893 115,410 Total cash, cash equivalents and restricted cash $ 157,804 $ 158,461

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Income Before Provision for (Benefit from) Income Taxes	Income before the provision for (benefit from) income taxes for the years ended December 31, 2021, 2020 and 2019 consisted of the following: Year Ended December 31, 2021 2020 2019 United States $ (32,059 ) $ (32,755 ) $ (40,055 ) Foreign 35,553 42,504 15,640 $ 3,494 $ 9,749 $ (24,415 )
Schedule of Provision for (Benefit from) Income Taxes	The provision for (benefit from) income taxes for the years ended December 31, 2021, 2020 and 2019 consisted of the following: Year Ended December 31, 2021 2020 2019 Current income tax provision (benefit): Federal $ (7,709 ) $ (24,409 ) $ 4,698 State (57 ) 228 (121 ) Foreign 8,984 11,655 (427 ) Total current income tax provision (benefit) 1,218 (12,526 ) 4,150 Deferred income tax provision (benefit): Federal 72 171 18,387 State — 97 5,100 Foreign (1,003 ) (2,794 ) (3,846 ) Total deferred income tax provision (benefit) (931 ) (2,526 ) 19,641 Total income tax provision (benefit) $ 287 $ (15,052 ) $ 23,791
Schedule of Reconciliation of U.S. Federal Statutory Rate to Effective Income Tax Rate	A reconciliation of the U.S. federal statutory rate to the Company’s effective income tax rate for the years ended December 31, 2021, 2020 and 2019 is as follows: Year Ended December 31, 2021 2020 2019 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % State taxes, net of federal tax benefit (61.9 ) (6.8 ) 9.8 Research and development tax credits 494.4 (37.6 ) 10.3 Permanent differences (20.6 ) (11.5 ) (1.6 ) Foreign tax rate differential (42.6 ) 7.3 10.2 Stock-based compensation (61.8 ) 8.6 5.0 Foreign taxes withheld 79.9 23.1 (9.6 ) Rate impact from CARES Act (69.2 ) (63.9 ) — Global intangible low-taxed income 75.3 35.7 (4.1 ) Withholding tax on repatriation of accumulated earnings of foreign subsidiaries 1.9 1.0 (0.1 ) Valuation allowance on deferred tax assets 146.2 (146.9 ) (144.2 ) Other, net 8.2 (7.5 ) 13.9 Foreign derived intangible income — — 3.9 Research and development costs (254.6 ) 20.0 (4.3 ) Uncertain tax positions (343.4 ) (3.2 ) (7.1 ) Non-deductible executive compensation expense 35.4 6.3 (0.5 ) Effective income tax rate 8.2 % (154.4 )% (97.4 )%
Schedule of Income Tax Effect of Each Type of Temporary Difference and Carryforward	The income tax effect of each type of temporary difference and carryforward as of December 31, 2021 and 2020 was as follows: December 31, 2021 2020 Deferred tax assets: Stock compensation $ 4,050 $ 4,710 Tax credit carryforwards 12,463 13,138 Net operating loss carryforward 4,695 1,504 Capitalized research and development costs 8,322 9,710 Inventory valuation 4,070 2,169 Accrued liabilities and reserves 5,680 4,825 Deferred revenue 295 796 Interest expense 2,436 — Other 607 724 Total deferred tax assets 42,618 37,576 Valuation Allowance (29,457 ) (24,463 ) Deferred tax assets, net of valuation allowance 13,161 13,113 Deferred tax liabilities: Depreciation (1,488 ) (2,092 ) Amortization (8,938 ) (10,932 ) Deferred costs (4,946 ) (3,444 ) Withholding tax on unremitted earnings (2,721 ) (2,650 ) Prepaid expenses (260 ) (127 ) Total deferred tax liabilities (18,353 ) (19,245 ) Net deferred tax liabilities $ (5,192 ) $ (6,132 )
Schedule of Changes in Balance of Gross Uncertain Tax Positions	The aggregate changes in the balance of gross uncertain tax positions, which excludes interest and penalties, for the years ended December 31, 2021, 2020 and 2019 were as follows: Balance at December 31, 2018 $ 2,746 Settlement/decreases related to tax positions taken during prior years (49 ) Increases related to tax positions taken during prior years 18,434 Increases related to tax positions taken during the current year 364 Balance at December 31, 2019 21,495 Expiration of statute of limitations (1,174 ) Settlement/decreases related to tax positions taken during prior years (2,815 ) Increases related to tax positions taken during prior years 155 Increases related to tax positions taken during the current year 249 Balance at December 31, 2020 17,910 Decreases related to tax positions taken during prior years (13,510 ) Increases related to tax positions taken during prior years 1,190 Increases related to tax positions taken during the current year 402 Balance at December 31, 2021 $ 5,992

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Schedule of Aggregate Principal Amount of Debt Outstanding	The aggregate principal amount of debt outstanding as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Term loans $ 278,225 $ 288,000 Revolving credit facility — 6,500 Total principal amount of debt outstanding $ 278,225 $ 294,500
Schedule of Current and Non-Current Debt Obligations	Current and non-current debt obligations reflected in the consolidated balance sheets as of December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Current liabilities: Term loans $ 3,000 $ 9,775 Revolving credit facility — 6,500 Current portion of principal payment obligations 3,000 16,275 Unamortized debt issuance costs, current portion (1,076 ) (1,104 ) Current portion of long-term debt, net of unamortized debt issuance costs $ 1,924 $ 15,171 Non-current liabilities: Term loans $ 275,225 $ 278,225 Unamortized debt issuance costs, non-current portion (1,032 ) (2,140 ) Long-term debt, net of current portion and unamortized debt issuance costs $ 274,193 $ 276,085
Schedule of Aggregate Minimum Future Principal Payments of Debt	As of December 31, 2021, aggregate minimum future principal payments of the Company’s debt are summarized as follows: Year Ending December 31, 2022 $ 3,000 2023 275,225 Thereafter — $ 278,225

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Schedule of Equitable Adjustment Payments	The below table provides details of these equitable adjustment payments: Equitable Adjustment Payments During the Year Ended Equitable Adjustment Liability(1) Dividend Declaration Dates Equitable Adjustment per share Year of Final Vesting December 31, 2021 December 31, 2020 December 31, 2019 As of December 31, 2021 As of December 31, 2020 November 30, 2017 $ 0.5802 2021 $ 44 $ 148 $ 426 — $ 30 May 10, 2017 1.1774 2021 52 178 618 — 31 December 27, 2016 2.3306 2020 2 303 1,286 — 2 June 17, 2016 0.5891 2020 — 54 259 — — November 30, 2014 0.3835 2018 — — 1 — — Total $ 98 $ 683 $ 2,590 $ — $ 63 (1) Net of estimated forfeitures. Amounts are included in accrued expenses and other current liabilities in the accompanying consolidated balance sheets.

Stock-based Compensation (Table

Stock-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Assumptions Used in Black-Scholes Option Pricing Model	The assumptions used in the Black-Scholes option-pricing model were as follows: Year Ended December 31, 2021 2020 2019 Risk-free interest rate 1.0%–1.3% 0.4%–0.7% 1.6%–2.5% Expected term (in years) 6.1 6.1 6.1-6.2 Expected volatility 37.7%–38.6% 29.3%–31.9% 28.8%–30.6% Expected dividend yield 0.0% 0.0% 0.0%
Summary of Option Activity	A summary of option activity for the year ended December 31, 2021 is as follows: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value (in years) Outstanding at January 1, 2021 7,120 $ 8.01 4.88 $ 9,367 Granted 151 7.54 Exercised (1,006 ) 2.25 Forfeited (346 ) 10.66 Outstanding at December 31, 2021 5,919 $ 8.82 4.36 $ 4,205 Options exercisable at December 31, 2021 5,609 $ 8.88 4.13 $ 4,059 Vested or expected to vest at December 31, 2021 5,900 $ 8.83 4.33 $ 4,196
Summary of RSU Activity	A summary of RSU activity for the year ended December 31, 2021 is as follows: Number of Shares Weighted- Average Grant Date Fair Value Aggregate Fair Value Unvested balance at January 1, 2021 4,231 $ 5.43 Granted 1,705 8.18 Vested (1,288 ) 6.12 $ 10,427 Forfeited (339 ) 5.01 Unvested balance at December 31, 2021 4,309 $ 6.34
Assumptions of Estimated Based on Monte Carlo Simulation Model	Compensation expense for PSUs is based on the estimated value of the awards on the grant date, and is recognized over the period from the grant date through the expected vest dates of each vesting condition, both of which were estimated based on a Monte Carlo simulation model applying the following key assumptions: Year Ended December 31, 2021 2020 Risk-free interest rate 0.2% 1.2% Volatility 78.6% 70.0% Dividend yield 0.0% 0.0% Cost of equity 12.0% 11.0%
Summary of PSU Activity	A summary of PSU activity for the year ended December 31, 2021 is as follows: Number of Shares Weighted- Average Grant Date Fair Value Aggregate Fair Value Unvested balance at January 1, 2021 737 $ 3.22 Granted 442 7.89 Vested (737 ) 3.22 $ 6,449 Forfeited — — Unvested balance at December 31, 2021 442 $ 7.89
Schedule of Stock-based Compensation Expense	The Company classified s tock-based compensation expense related to stock options, RSUs, PSUs and SARs for the years ended December 31, 2021, 2020 and 2019 in the consolidated statements of operations and comprehensive income (loss) as follows: Year Ended December 31, 2021 2020 2019 Cost of revenue $ 137 $ 153 $ 216 Research and development expenses 2,665 2,447 1,569 Selling, general and administrative 12,017 10,555 8,036 $ 14,819 $ 13,155 $ 9,821 The Company recognized s tock-based compensation expense for the years ended December 31, 2021, 2020 and 2019 in the consolidated balance sheets as follows: Year Ended December 31, 2021 2020 2019 Change in fair value of SAR liability $ — $ 229 $ (1,123 ) Recognized as additional paid-in capital 14,819 12,926 10,944 Total stock-based compensation $ 14,819 $ 13,155 $ 9,821

Net Income (Loss) per Share (Ta

Net Income (Loss) per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Income (Loss) Per Share Attributable to Common Stockholders	The Company calculated b asic and diluted net income (loss) per share attributable to common stockholders as follows: Year Ended December 31, 2021 2020 2019 Numerator: Net income (loss) attributable to common stockholders, basic and diluted $ 3,207 $ 24,801 $ (48,206 ) Denominator: Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, basic 85,253 83,465 83,853 Dilutive effect of stock options 1,526 1,050 — Dilutive effect of restricted stock units 2,078 763 — Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, diluted 88,857 85,278 83,853 Net income (loss) per share attributable to common stockholders: Basic $ 0.04 $ 0.30 $ (0.57 ) Diluted $ 0.04 $ 0.29 $ (0.57 )
Schedule of Potential Common Shares Excluded from the Computation of Diluted Net Income (Loss) Per Share Attributable to Common Stockholders	The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net income (loss) per share attributable to common stockholders for the periods presented because including them would have been anti-dilutive: Year Ended December 31, 2021 2020 2019 Options to purchase common stock 3,411 4,119 4,641 Unvested restricted stock units 712 1,030 1,516 Unvested performance-based stock units — 983 —

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2021
Revenue From Contract With Customer [Abstract]
Summary of Disaggregation of Revenue Based on Geographic Locations Determined by Customer's Shipping Address	The Company also disaggregates its revenue based on geographic locations of its customers, as determined by the customer’s shipping address, summarized as follows: Year Ended December 31, 2021 2020 2019 North America: United States $ 154,765 $ 127,217 $ 103,451 Canada 66,537 38,960 36,466 Total North America 221,302 166,177 139,917 Latin America 27,841 34,926 24,043 Europe, Middle East and Africa: 30,378 35,933 38,154 Asia-Pacific Australia 89,548 116,661 42,218 Other 32,256 39,549 37,965 Total Asia-Pacific 121,804 156,210 80,183 Total revenue ( 1) $ 401,325 $ 393,246 $ 282,297 (1) Other than the United States, Canada and Australia, no individual countries represented 10% or
Summary of Disaggregates of Revenue Based on Product Line	The Company also disaggregates its revenue based on product line summarized as follows: Year Ended December 31, 2021 2020 2019 Product revenue: Wireless $ 170,233 $ 111,255 $ 58,234 Fixed telco 66,017 96,904 38,734 Cable 117,692 137,924 144,409 Total product revenue 353,942 346,083 241,377 Service revenue Wireless 5,538 7,348 1,701 Fixed telco 5,034 1,924 773 Cable 36,811 37,891 38,446 Total service revenue 47,383 47,163 40,920 Total revenue $ 401,325 $ 393,246 $ 282,297

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Schedule of Property and Equipment, Net by Location	The Company’s property and equipment, net by location was as follows: December 31, 2021 2020 United States $ 17,089 $ 20,988 China 3,118 2,986 Australia 2,027 2,849 Other 1,274 2,057 Total property and equipment, net $ 23,508 $ 28,880

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments under Non-cancelable Operating Leases	Future minimum lease payments under non-cancelable operating leases as of December 31, 2021 were as follows: Year Ending December 31, 2022 $ 2,138 2023 2,028 2024 1,116 2025 874 2026 795 Thereafter 511 $ 7,462

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Significant Accounting Policies [Line Items]
Restricted cash	$ 3,101,000	$ 1,006,000
Write off of uncollectible receivables			$ 950,000
Percentage of fair value of reporting unit	50.00%
Intangible assets amortization method	straight-line method
Standard product warranty description	The Company’s products are covered by a warranty for software and hardware for periods ranging from 90 days to one year
Extended product warranty description	The Company offers an extended warranty for periods typically of one to three years for agreed-upon fees.
Foreign currency transaction (losses) gains	$ (2,113,000)	452,000	298,000
Valuation allowance	29,457,000	24,463,000
Deferred tax asset valuation allowance increase (decrease)	3,727,000
Income tax charge	$ 287,000	(15,052,000)	23,791,000
Change in accounting principle accounting standards update adopted	true
Change in Accounting Principle, Accounting Standards Update, Early Adoption	true
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect	true
Accounting Standards Update Description	ASU 2020-06
ASC Update No. 2019-12
Significant Accounting Policies [Line Items]
Change in accounting principle accounting standards update adopted	true
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect	true
Accounting Standards Update Description	ASU 2019-12
Global Intangible Low Taxed Income
Significant Accounting Policies [Line Items]
Income tax charge	$ 2,630,000	3,483,000	942,000
United States
Significant Accounting Policies [Line Items]
Valuation allowance	28,190,000
Deferred tax asset valuation allowance increase (decrease)	3,727,000
Foreign
Significant Accounting Policies [Line Items]
Valuation allowance	1,267,000	1,267,000
Deferred tax asset valuation allowance increase (decrease)		1,267,000
Interest Income
Significant Accounting Policies [Line Items]
Other revenue	$ 20,000	64,000	160,000
Software
Significant Accounting Policies [Line Items]
Warranty period	90 days
Hardware
Significant Accounting Policies [Line Items]
Warranty period	1 year
Minimum
Significant Accounting Policies [Line Items]
Intangible assets, estimated useful lives	3 years
Product warranties period for software and hardware	90 days
Extended product warranty period for renewals of maintenance and support contracts	1 year
Maximum
Significant Accounting Policies [Line Items]
Intangible assets, estimated useful lives	10 years
Product warranties period for software and hardware	1 year
Extended product warranty period for renewals of maintenance and support contracts	3 years
Maintenance and support services and professional services revenue, recognition period	5 years
Trial Systems at Customers' Sites
Significant Accounting Policies [Line Items]
Property and equipment useful life	2 years
Software Licenses
Significant Accounting Policies [Line Items]
Intangible assets amortization method	straight-line method
Software Licenses | Minimum
Significant Accounting Policies [Line Items]
Intangible assets, estimated useful lives	3 years
Software Licenses | Maximum
Significant Accounting Policies [Line Items]
Intangible assets, estimated useful lives	4 years
Accounts Receivable, Extended Payment Terms
Significant Accounting Policies [Line Items]
Reserve for credit losses	$ 0	0	0
Write off of uncollectible receivables	0	0	$ 0
Certificates of Deposit
Significant Accounting Policies [Line Items]
Restricted cash	1,001,000	$ 1,006,000
Cash
Significant Accounting Policies [Line Items]
Restricted cash	$ 2,100,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Reconciliation of Cash, Cash Equivalents and Restricted Cash in Accompanying Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019	[1]	Dec. 31, 2018
Accounting Policies [Abstract]
Cash and cash equivalents	$ 154,703		$ 157,455
Restricted cash included in other assets	$ 3,101		$ 1,006
Restricted Cash and Cash Equivalents, Noncurrent, Asset, Statement of Financial Position [Extensible List]	Other assets		Other assets
Cash and cash equivalents, restricted cash	$ 157,804	[1]	$ 158,461	[1]	$ 114,657		$ 281,606
[1]	See Note 2 of the accompanying notes for a reconciliation of the ending balance of cash, cash equivalents and restricted cash shown in these consolidated statements of cash flows.

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current portion of accounts receivable, net:
Current portion of accounts receivable, net	$ 85,774	$ 94,124
Accounts receivable, net of current portion:
Accounts receivable, net of current portion	115	143
Accounts receivable	85,889	94,267
Accounts Receivable, Net
Current portion of accounts receivable, net:
Current portion of accounts receivable, net	85,689	93,480
Accounts Receivable, Extended Payment Terms
Current portion of accounts receivable, net:
Current portion of accounts receivable, net	$ 85	$ 644

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Summary of Changes in Provision for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Provision for doubtful accounts at beginning of year	$ 58	$ 20	$ 410
Provisions and recoveries	59	38	560
Write-offs			(950)
Provision for doubtful accounts at end of year	$ 117	$ 58	$ 20

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Property and Equipment Assets (Details)	12 Months Ended
	Dec. 31, 2021
Computers and Purchased Software | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life	3 years
Computers and Purchased Software | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life	4 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment useful life	7 years
Property and equipment useful life	Shorter of lease term or 7 years
Furniture and Fixtures | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life	6 years
Furniture and Fixtures | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life	8 years
Machinery and Equipment | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life	3 years
Machinery and Equipment | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life	10 years
Building
Property Plant And Equipment [Line Items]
Property and equipment useful life	40 years
Building Improvements | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life	5 years
Building Improvements | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life	40 years
Trial Systems at Customers' Sites
Property Plant And Equipment [Line Items]
Property and equipment useful life	2 years

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Schedule of Significant Customers Represent 10% or More of Revenue or Accounts Receivable (Details) - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue | Customer A
Concentration Risk [Line Items]
Concentration risk percentage	22.00%	11.00%
Revenue | Customer D
Concentration Risk [Line Items]
Concentration risk percentage		20.00%	12.00%
Revenue | Customer E
Concentration Risk [Line Items]
Concentration risk percentage			14.00%
Accounts Receivable | Customer A
Concentration Risk [Line Items]
Concentration risk percentage	21.00%	14.00%
Accounts Receivable | Customer B
Concentration Risk [Line Items]
Concentration risk percentage	19.00%
Accounts Receivable | Customer C
Concentration Risk [Line Items]
Concentration risk percentage	10.00%

Summary of Significant Accou_10

Summary of Significant Accounting Policies - Summary of Changes in Amount Reserved for Warranty Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Warranty reserve at beginning of year	$ 2,354	$ 2,448	$ 926
Provisions	2,339	2,745	3,603
Acquired warranty reserve			1,867
Charges	(2,301)	(2,839)	(3,948)
Warranty reserve at end of year	$ 2,392	$ 2,354	$ 2,448

Business Acquisition - Addition

Business Acquisition - Additional Information (Details) $ in Thousands, $ in Thousands	Jul. 01, 2019USD ($)	Jul. 01, 2019AUD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Business Acquisition [Line Items]
Goodwill			$ 50,177	$ 50,177	$ 50,347
Net income (loss)			$ 3,207	$ 24,801	(48,206)
NetComm
Business Acquisition [Line Items]
Business combination acquisition of equity interests percentage	100.00%
Cash consideration	$ 112,674	$ 161,963
Exchange rate	0.700
Identifiable intangible assets	$ 44,000
Weighted average life of identifiable intangible assets	8 years 2 months 12 days	8 years 2 months 12 days
Goodwill	$ 50,177
Net revenues					75,769
Net income (loss)					1,424
Transaction costs related to acquisition					$ 3,494
NetComm | Developed Technology
Business Acquisition [Line Items]
Intangible assets, estimated useful lives	7 years	7 years
NetComm | Customer Relationships
Business Acquisition [Line Items]
Intangible assets, estimated useful lives	10 years	10 years
NetComm | Trade Name
Business Acquisition [Line Items]
Intangible assets, estimated useful lives	3 years	3 years

Goodwill and Intangibles - Sche

Goodwill and Intangibles - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Finite Lived Intangible Assets [Line Items]
Net Carrying Amount	$ 31,144
NetComm
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	45,832	$ 44,432
Accumulated Amortization	(14,688)	(8,588)
Net Carrying Amount	31,144	35,844
Developed Technology | NetComm
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	25,000	25,000
Accumulated Amortization	(8,930)	(5,358)
Net Carrying Amount	16,070	19,642
Customer Relationships | NetComm
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	18,000	18,000
Accumulated Amortization	(4,500)	(2,700)
Net Carrying Amount	13,500	15,300
Trade Name | NetComm
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,000	1,000
Accumulated Amortization	(830)	(498)
Net Carrying Amount	170	502
Purchased Software | NetComm
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,832	432
Accumulated Amortization	(428)	(32)
Net Carrying Amount	$ 1,404	$ 400

Goodwill and Intangibles - Sc_2

Goodwill and Intangibles - Schedule of Amortization Expense on Existing Intangible Assets (Details) $ in Thousands	Dec. 31, 2021USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
2022	$ 5,963
2023	5,764
2024	5,660
2025	5,651
2026	3,606
Thereafter	4,500
Net Carrying Amount	$ 31,144

Goodwill and Intangibles - Summ

Goodwill and Intangibles - Summary of Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Finite Lived Intangible Assets [Line Items]
Amortization expense	$ 6,100	$ 5,736
Product Cost of Revenue
Finite Lived Intangible Assets [Line Items]
Amortization expense	3,572	3,571
Research and Development
Finite Lived Intangible Assets [Line Items]
Amortization expense	396	32
Selling, General and Administrative Expenses
Finite Lived Intangible Assets [Line Items]
Amortization expense	$ 2,132	$ 2,133

Goodwill and Intangibles - Sc_3

Goodwill and Intangibles - Schedule of Carrying Value of Goodwill (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Beginning Balance	$ 50,347
Adjustment recorded to preliminary purchase price allocation	(170)
Ending Balance	$ 50,177

Goodwill and Intangible Assets

Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill	$ 50,177	$ 50,177	$ 50,347

Inventory - Schedule of Invento

Inventory - Schedule of Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 53,934	$ 50,904
Work in process		19
Finished goods:
Manufactured finished goods	29,597	49,764
Deferred inventory costs	1,297	517
Total inventory	$ 84,828	$ 101,204

Property and Equipment - Summar

Property and Equipment - Summary of Components of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 88,965	$ 88,758
Less: Accumulated depreciation and amortization	(65,457)	(59,878)
Property and equipment, net	23,508	28,880
Computers and Purchased Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	25,775	24,865
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	4,198	4,148
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,672	2,644
Machinery and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	37,325	36,701
Land
Property Plant And Equipment [Line Items]
Property and equipment, gross	3,091	3,091
Building
Property Plant And Equipment [Line Items]
Property and equipment, gross	4,765	4,765
Building Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	7,291	7,244
Trial Systems at Customers' Sites
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,848	$ 5,300

Property and Equipment - Additi

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Depreciation and amortization expense on property and equipment	$ 9,580	$ 12,234	$ 11,870
Trial Systems
Property Plant And Equipment [Line Items]
Transfers from (into) inventory into (from) property and equipment	(1,452)	(1,259)	(502)
Equipment
Property Plant And Equipment [Line Items]
Transfers from (into) inventory into (from) property and equipment	$ 993	$ 805	$ 261

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Accrued compensation and related taxes	$ 21,751	$ 22,785
Accrued warranty (see Note 2)	2,392	2,354
Inventory-related accruals	8,391	855
Other accrued expenses	8,848	13,799
Total accrued expenses and other current liabilities	$ 41,382	$ 39,793

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Assets fair value	$ 94,798	$ 115,410
Liabilities:
Liabilities fair value	358	493
Certificates of Deposit-Restricted Cash
Assets:
Assets fair value	1,001	1,006
Money Market Mutual Funds
Assets:
Assets fair value	93,792	114,404
Foreign Currency Forward Contracts
Assets:
Assets fair value	5
Level 1
Assets:
Assets fair value	93,792	114,404
Level 1 | Money Market Mutual Funds
Assets:
Assets fair value	93,792	114,404
Level 2
Assets:
Assets fair value	1,006	1,006
Level 2 | Certificates of Deposit-Restricted Cash
Assets:
Assets fair value	1,001	1,006
Level 2 | Foreign Currency Forward Contracts
Assets:
Assets fair value	5
Level 3
Liabilities:
Liabilities fair value	358	493
SARs | Share Based Compensation Liability
Liabilities:
Liabilities fair value	358	493
SARs | Level 3 | Share Based Compensation Liability
Liabilities:
Liabilities fair value	$ 358	$ 493

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value, assets, transfers from Level 1 to Level 2	$ 0	$ 0	$ 0
Fair value, assets, transfers from Level 2 to Level 1	0	0	0
Fair value, liabilities, transfers from Level 1 to Level 2	0	0	0
Fair value, liabilities, transfers from Level 2 to Level 1	0	0	0
Fair value, assets, transfers into Level 3	0	0	0
Fair value, assets, transfers out of Level 3	0	0	0
Fair value, liabilities, transfers into Level 3	$ 0	$ 0	$ 0

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Changes in Fair Values of SARs Liability (Details) - Level 3 - SARs - Share Based Compensation Liability - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value at beginning of the year	$ 493	$ 264	$ 1,387
Change in fair value		229	(1,123)
Exercises	(135)
Fair value at end of year	$ 358	$ 493	$ 264

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Company's Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019	[1]	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Cash	$ 60,911		$ 43,051
Cash equivalents and restricted cash:
Restricted cash	3,101		1,006
Money market mutual funds	93,792		114,404
Total cash equivalents and restricted cash	96,893		115,410
Cash and cash equivalents, restricted cash	$ 157,804	[1]	$ 158,461	[1]	$ 114,657		$ 281,606
[1]	See Note 2 of the accompanying notes for a reconciliation of the ending balance of cash, cash equivalents and restricted cash shown in these consolidated statements of cash flows.

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2020AUD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2021EUR (€)	Dec. 31, 2020EUR (€)
Australian Subsidiary
Derivatives Fair Value [Line Items]
Fair value of derivatives amount recognized	$ 1,613,000
Australian Subsidiary | Cost of Goods Sold
Derivatives Fair Value [Line Items]
Fair value of derivatives amount recognized	124,000
Australian Subsidiary | Research and Development Expense
Derivatives Fair Value [Line Items]
Fair value of derivatives amount recognized	890,000
Australian Subsidiary | Selling, General and Administrative Expenses
Derivatives Fair Value [Line Items]
Fair value of derivatives amount recognized	599,000
Australian Subsidiary | Cash Flow Hedges
Derivatives Fair Value [Line Items]
Amount of gain reclassified from other comprehensive income (loss)	752,000
Foreign Currency Forward Contracts | Prepaid Expenses and Other Current Assets
Derivatives Fair Value [Line Items]
Derivatives asset fair value			$ 5,000
Foreign Currency Forward Contracts | Accrued Expenses And Other Current Liabilities
Derivatives Fair Value [Line Items]
Liability derivatives	0
Foreign Currency Forward Contracts | Irish Subsidiary
Derivatives Fair Value [Line Items]
Outstanding notional amounts | €				€ 241,000	€ 0
Foreign Currency Forward Contracts | Australian Subsidiary | Cash Flow Hedges
Derivatives Fair Value [Line Items]
Outstanding notional amounts	$ 0		$ 0
Foreign Currency Forward Contracts One | Australian Subsidiary | Cash Flow Hedges
Derivatives Fair Value [Line Items]
Derivative notional amounts settled		$ 8,500
Foreign Currency Forward Contracts Two | Australian Subsidiary | Cash Flow Hedges
Derivatives Fair Value [Line Items]
Derivative notional amounts settled		$ 5,000

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Before Provision for (Benefit from) Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
United States	$ (32,059)	$ (32,755)	$ (40,055)
Foreign	35,553	42,504	15,640
Income (loss) before provision for (benefit from) income taxes	$ 3,494	$ 9,749	$ (24,415)

Income Taxes - Schedule of Prov

Income Taxes - Schedule of Provision for (Benefit from) Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current income tax provision (benefit):
Federal	$ (7,709)	$ (24,409)	$ 4,698
State	(57)	228	(121)
Foreign	8,984	11,655	(427)
Total current income tax provision (benefit)	1,218	(12,526)	4,150
Deferred income tax provision (benefit):
Federal	72	171	18,387
State		97	5,100
Foreign	(1,003)	(2,794)	(3,846)
Total deferred income tax provision (benefit)	(931)	(2,526)	19,641
Total income tax provision (benefit)	$ 287	$ (15,052)	$ 23,791

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of U.S. Federal Statutory Rate to Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21.00%	21.00%	21.00%
State taxes, net of federal tax benefit	(61.90%)	(6.80%)	9.80%
Research and development tax credits	494.40%	(37.60%)	10.30%
Permanent differences	(20.60%)	(11.50%)	(1.60%)
Foreign tax rate differential	(42.60%)	7.30%	10.20%
Stock-based compensation	(61.80%)	8.60%	5.00%
Foreign taxes withheld	79.90%	23.10%	(9.60%)
Rate impact from CARES Act	(69.20%)	(63.90%)
Global intangible low-taxed income	75.30%	35.70%	(4.10%)
Withholding tax on repatriation of accumulated earnings of foreign subsidiaries	1.90%	1.00%	(0.10%)
Valuation allowance on deferred tax assets	146.20%	(146.90%)	(144.20%)
Other, net	8.20%	(7.50%)	13.90%
Foreign derived intangible income			3.90%
Research and development costs	(254.60%)	20.00%	(4.30%)
Uncertain tax positions	(343.40%)	(3.20%)	(7.10%)
Non-deductible executive compensation expense	35.40%	6.30%	(0.50%)
Effective income tax rate	8.20%	(154.40%)	(97.40%)

Income Taxes - Schedule of In_2

Income Taxes - Schedule of Income Tax Effect of Each Type of Temporary Difference and Carryforward (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Stock compensation	$ 4,050	$ 4,710
Tax credit carryforwards	12,463	13,138
Net operating loss carryforward	4,695	1,504
Capitalized research and development costs	8,322	9,710
Inventory valuation	4,070	2,169
Accrued liabilities and reserves	5,680	4,825
Deferred revenue	295	796
Interest expense	2,436
Other	607	724
Total deferred tax assets	42,618	37,576
Valuation Allowance	(29,457)	(24,463)
Deferred tax assets, net of valuation allowance	13,161	13,113
Deferred tax liabilities:
Depreciation	(1,488)	(2,092)
Amortization	(8,938)	(10,932)
Deferred costs	(4,946)	(3,444)
Withholding tax on unremitted earnings	(2,721)	(2,650)
Prepaid expenses	(260)	(127)
Total deferred tax liabilities	(18,353)	(19,245)
Net deferred tax liabilities	$ (5,192)	$ (6,132)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	Mar. 27, 2020	Mar. 26, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes Disclosure [Line Items]
Valuation Allowance			$ 29,457	$ 24,463
Deferred tax asset valuation allowance increase (decrease)			3,727
Percentage of taxable income offset by NOL carryovers and carrybacks	100.00%
Tax benefit of due to the revaluation of deferred tax assets due to the carryback of U.S. net operating loss			7,097	23,518
Interest expense deduction, percentage of adjusted taxable income	50.00%	30.00%
Income tax charges related to global intangible low taxed income			2,630	3,483	$ 942
Tax expense (benefit) from newly issued guidance			2,869
Undistributed earnings amount			27,211
Deferred tax liability			2,721
Foreign withholding taxes on unremitted earnings			113,350
Liability recorded for potential penalties and interest			248	2,260
Unrecognized tax benefits			5,992	17,910	21,495	$ 2,746
Unrecognized tax benefits that would impact effective tax rate			5,359
Unrecognized tax benefits change in next 12 months due to the expiration of the statute of limitations			$ 3,129
Minimum
Income Taxes Disclosure [Line Items]
Statute of limitation year			3 years
Maximum
Income Taxes Disclosure [Line Items]
Statute of limitation year			4 years
Other Income (Expense)
Income Taxes Disclosure [Line Items]
Interest and penalties related to uncertain tax positions			$ (2,012)	614	$ 1,278
Start Year | United States
Income Taxes Disclosure [Line Items]
Examination tax year			2018
Start Year | Irish Subsidiary
Income Taxes Disclosure [Line Items]
Examination tax year			2017
Start Year | China
Income Taxes Disclosure [Line Items]
Examination tax year			2011
Start Year | Australia
Income Taxes Disclosure [Line Items]
Examination tax year			2017
End Year | United States
Income Taxes Disclosure [Line Items]
Examination tax year			2021
End Year | Irish Subsidiary
Income Taxes Disclosure [Line Items]
Examination tax year			2021
End Year | China
Income Taxes Disclosure [Line Items]
Examination tax year			2021
End Year | Australia
Income Taxes Disclosure [Line Items]
Examination tax year			2021
United States
Income Taxes Disclosure [Line Items]
Valuation Allowance			$ 28,190
Deferred tax asset valuation allowance increase (decrease)			3,727
China and Germany
Income Taxes Disclosure [Line Items]
Valuation Allowance			1,267	1,267
Deferred tax asset valuation allowance increase (decrease)				$ 1,267
Net operating loss carryforwards			9,745
China and Germany | Indefinite Tax Year
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards			6,814
China and Germany | Tax Year 2024
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards			$ 2,931
Net operating loss carryforwards, expiration year			2024
Federal
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards			$ 714
Research and development tax credit carryforwards			$ 1,293
Research and development tax credit carryforwards expiration year			2030
State
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards			$ 35,576
Research and development tax credit carryforwards			$ 12,503
Research and development tax credit carryforwards expiration year			2030
State | Tax Year 2030
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards			$ 21,507
Net operating loss carryforwards, expiration year			2031
State | Indefinite Tax Year
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards			$ 14,069

Income Taxes - Schedule of Chan

Income Taxes - Schedule of Changes in Balance of Gross Uncertain Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Balance	$ 17,910	$ 21,495	$ 2,746
Settlement/decreases related to tax positions taken during prior years		(2,815)	(49)
Expiration of statute of limitations		(1,174)
Decreases related to tax positions taken during prior years	(13,510)
Increases related to tax positions taken during prior years	1,190	155	18,434
Increases related to tax positions taken during the current year	402	249	364
Balance	$ 5,992	$ 17,910	$ 21,495

Debt - Schedule of Aggregate Pr

Debt - Schedule of Aggregate Principal Amount of Debt Outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total principal amount of debt outstanding	$ 278,225	$ 294,500
Term Loan
Debt Instrument [Line Items]
Total principal amount of debt outstanding	$ 278,225	288,000
Revolving Credit Facility
Debt Instrument [Line Items]
Total principal amount of debt outstanding		$ 6,500

Debt - Schedule of Current and

Debt - Schedule of Current and Non-Current Debt Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current liabilities:
Current portion of principal payment obligations	$ 3,000	$ 16,275
Revolving credit facility		6,500
Unamortized debt issuance costs, current portion	(1,076)	(1,104)
Current portion of long-term debt, net of unamortized debt issuance costs	1,924	15,171
Non-current liabilities:
Unamortized debt issuance costs, non-current portion	(1,032)	(2,140)
Long-term debt, net of current portion and unamortized debt issuance costs	274,193	276,085
Term Loan
Current liabilities:
Current portion of principal payment obligations	3,000	9,775
Non-current liabilities:
Non-current portion of principal payment obligations	$ 275,225	$ 278,225

Debt - Schedule of Aggregate Mi

Debt - Schedule of Aggregate Minimum Future Principal Payments of Debt (Details) $ in Thousands	Dec. 31, 2021USD ($)
Debt Disclosure [Abstract]
2022	$ 3,000
2023	275,225
Aggregate minimum future principal payments of debt	$ 278,225

Debt - Additional Information (

Debt - Additional Information (Details)	Dec. 20, 2016USD ($)	Jul. 01, 2015USD ($)Installment	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Outstanding borrowings			$ 278,225,000
Outstanding borrowings				$ 6,500,000
JPMorgan Chase Bank, N. A.
Debt Instrument [Line Items]
Debt instrument, interest rate description			Borrowings under the facilities bear interest at a floating rate, which can be either a Eurodollar rate plus an applicable margin or, at the Company’s option, a base rate (defined as the highest of (x) the JPMorgan Chase, N.A. prime rate, (y) the federal funds effective rate, plus one-half percent (0.50%) per annum and (z) a one-month Eurodollar rate plus 1.00% per annum) plus an applicable margin. The applicable margin for borrowings under the Term Loan is 4.00% per annum for Eurodollar rate loans (subject to a 1.00% per annum interest rate floor) and 3.00% per annum for base rate loans. The applicable margin for borrowings under the revolving credit facility was 1.75% per annum for Eurodollar rate loans and 0.75% per annum for base rate loans, subject to reduction based on the Company’s maintaining of specified net leverage ratios. The interest rates payable under the facilities are subject to an increase of 2.00% per annum during the continuance of any payment default.
Debt instrument prepayment description			In addition, the Company is required to make mandatory prepayments under the facilities with respect to (i) 100% of the net cash proceeds from certain asset dispositions (including casualty and condemnation events) by the Company or certain of its subsidiaries, subject to certain exceptions and reinvestment provisions, (ii) 100% of the net cash proceeds from the issuance or incurrence of any additional debt by the Company or certain of its subsidiaries, subject to certain exceptions, and (iii) 50% of the Company’s excess cash flow, as defined in the credit agreement, subject to reduction upon its achievement of specified performance targets. In accordance with these provisions, based on the results for the year ended December 31, 2020, a mandatory prepayment of $6,775 was paid on April 2, 2021. This amount was included in the current portion of long-term debt, net of unamortized debt issuance costs on the consolidated balance sheet as of December 31, 2020. Based on results for the year ended December 31, 2021, no mandatory prepayment will be required in 2022.
Percentage of net proceeds from asset dispositions to be used for mandatory prepayment	100.00%
Percentage of net cash proceeds from issuances or incurrence of additional Debt to be used for mandatory prepayment	100.00%
Percentage on excess cash flow for mandatory prepayments of debt	50.00%
Debt instrument, mandatory prepayment of debt payable				6,775,000
JPMorgan Chase Bank, N. A. | Minimum
Debt Instrument [Line Items]
Line of credit facility borrowing capacity utilized percentage			30.00%
Term Loan | JPMorgan Chase Bank, N.A. and Barclays Bank PLC and Various Lenders
Debt Instrument [Line Items]
Maximum borrowing amount under facility	$ 300,000,000
Outstanding borrowings			$ 278,225,000	$ 288,000,000
Term Loan | JPMorgan Chase Bank, N. A.
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage	4.00%
Debt instrument, interest rate description			As of December 31, 2021 and 2020, the interest rate on the Term Loan was 5.00% per annum, which was based on a one-month and six-month Eurodollar rate, respectively, of 1.00% per annum plus the applicable margin of 4.00% per annum for Eurodollar rate loans.
Debt instrument, effective interest rate percentage			5.00%	5.00%
Debt issuance costs	$ 7,811,000
Debt instrument, principal payment			$ 9,775,000	$ 3,000,000	$ 3,000,000
Interest expense, including amortization of debt issuance costs			$ 15,519,000	$ 16,493,000	19,728,000
Debt instrument, maturity date	Dec. 20, 2023
Original principal amount of term loan amortization percentage	1.00%
Principal amount of loan	$ 300,000,000
Term Loan | JPMorgan Chase Bank, N. A. | Eurodollar Rate
Debt Instrument [Line Items]
Debt instrument, variable interest rate percentage			4.00%	4.00%
Debt instrument, effective interest rate percentage			1.00%	1.00%
Term Loan | JPMorgan Chase Bank, N. A. | Floor Rate
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage	1.00%
Term Loan | JPMorgan Chase Bank, N. A. | Base Rate
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage	3.00%
Commercial Mortgage Loan
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage		3.50%
Debt instrument, principal payment				$ 6,644,000	314,000
Interest expense, including amortization of debt issuance costs				120,000	249,000
Debt instrument, maturity date		Jul. 1, 2020
Principal amount of loan		$ 7,950,000
Debt instrument, number of periodic payment installments | Installment		60
Debt instrument, principal and interest payment		$ 46,000
Debt instrument payment, amortization period		20 years
Debt issuance costs		$ 45,000
Revolving Credit Facility | JPMorgan Chase Bank, N.A. and Barclays Bank PLC and Various Lenders
Debt Instrument [Line Items]
Maximum borrowing amount under facility	$ 25,000,000
Outstanding borrowings				6,500,000
Collateral amount			$ 2,100,000
Revolving Credit Facility | JPMorgan Chase Bank, N. A.
Debt Instrument [Line Items]
Debt instrument, interest rate increase	2.00%
Payment of quarterly commitment fees percentage			0.25%
Interest expense related to the fee for the unused amount			$ 46,000	52,000	$ 59,000
Revolving Credit Facility | JPMorgan Chase Bank, N. A. | Federal Funds Effective Rate
Debt Instrument [Line Items]
Debt instrument, variable interest rate percentage	0.50%
Revolving Credit Facility | JPMorgan Chase Bank, N. A. | Eurodollar Rate
Debt Instrument [Line Items]
Debt instrument, variable interest rate percentage	1.00%
Debt instrument, interest rate stated percentage	1.75%
Revolving Credit Facility | JPMorgan Chase Bank, N. A. | Base Rate
Debt Instrument [Line Items]
Debt instrument, interest rate stated percentage	0.75%
Stand-by Letter of Credit | JPMorgan Chase Bank, N.A. and Barclays Bank PLC and Various Lenders
Debt Instrument [Line Items]
Line of credit facility, used as collateral amount				$ 1,454,000

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Equitable Adjustment Payments (Details) - Vested Equity Awards - USD ($) $ / shares in Units, $ in Thousands	May 10, 2017	Dec. 27, 2016	Jun. 17, 2016	Nov. 30, 2014	Nov. 30, 2017	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Class Of Stock [Line Items]
Equitable Adjustment Payments						$ 98	$ 683	$ 2,590
Accrued Expenses And Other Current Liabilities
Class Of Stock [Line Items]
Equitable Adjustment Liability							63
November 30, 2017 Special Dividend
Class Of Stock [Line Items]
Dividend Declaration Dates					Nov. 30, 2017
Equitable Adjustment per share					$ 0.5802
Year of Final Vesting					2021
Equitable Adjustment Payments						44	148	426
November 30, 2017 Special Dividend | Accrued Expenses And Other Current Liabilities
Class Of Stock [Line Items]
Equitable Adjustment Liability							30
May 10, 2017 Special Dividend
Class Of Stock [Line Items]
Dividend Declaration Dates	May 10, 2017
Equitable Adjustment per share	$ 1.1774
Year of Final Vesting	2021
Equitable Adjustment Payments						52	178	618
May 10, 2017 Special Dividend | Accrued Expenses And Other Current Liabilities
Class Of Stock [Line Items]
Equitable Adjustment Liability							31
December 27, 2016 Special Dividend
Class Of Stock [Line Items]
Dividend Declaration Dates		Dec. 27, 2016
Equitable Adjustment per share		$ 2.3306
Year of Final Vesting		2020
Equitable Adjustment Payments						$ 2	303	1,286
December 27, 2016 Special Dividend | Accrued Expenses And Other Current Liabilities
Class Of Stock [Line Items]
Equitable Adjustment Liability							2
June 17, 2016 Special Dividend
Class Of Stock [Line Items]
Dividend Declaration Dates			Jun. 17, 2016
Equitable Adjustment per share			$ 0.5891
Year of Final Vesting			2020
Equitable Adjustment Payments							$ 54	259
November 30, 2014 Special Dividend
Class Of Stock [Line Items]
Dividend Declaration Dates				Nov. 30, 2014
Equitable Adjustment per share				$ 0.3835
Year of Final Vesting				2018
Equitable Adjustment Payments								$ 1

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 21, 2019	Dec. 19, 2017	Nov. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares authorized	500,000,000	500,000,000			500,000,000
Common stock, par value	$ 0.001	$ 0.001			$ 0.001
Cash proceeds received upon the exercise of options	$ 2,262,000	$ 1,195,000	$ 2,687,000
Fair value of SAR liability	358,000	$ 493,000
Unrecognized compensation cost	$ 21,705,000
Weighted-average period of unrecognized compensation cost expected to be recognized	2 years 5 months 23 days
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock repurchase program, common stock remaining authorized to be repurchased	$ 61,423,000
Stock repurchase program, stock repurchased, shares	1,671,000	1,227,000	495,000
Stock repurchase program, stock repurchased, value	$ 8,819,000	$ 3,031,000	$ 1,795,000
November 2014 Special Dividend
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends, declared date	Nov. 30, 2014
June 2016 Special Dividend
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends, declared date	Jun. 17, 2016
December 2016 Special Dividend
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends, declared date	Dec. 21, 2016
May 2017 Special Dividend
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends, declared date	May 10, 2017
November 2017 Special Dividend
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends, declared date	Nov. 30, 2017
Board of Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock cash dividends declared	$ 0
Maximum | Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock repurchase program, common stock authorized to be repurchased				$ 75,000,000
2011 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award termination period	2017-12
Number of remaining shares available for grant	2,855,000
2017 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of remaining shares available for grant	9,810,000
Common stock, initially reserved for future issuance	10,670,000					7,161,000
Number of shares authorized for grant	20,480,000					18,746,000
2017 Stock Incentive Plan | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issued in period	20,000,000
Percentage of number of shares issued in period	4.00%
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average grant date fair value per share of options	$ 2.88	$ 1.42	$ 2.13
Cash proceeds received upon the exercise of options	$ 2,263,000	$ 1,195,000	$ 2,687,000
Intrinsic value of stock options exercised	$ 5,594,000	$ 1,746,000	$ 6,970,000
Stock Options | 2011 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award expiration period	10 years
Stock Options | 2011 Stock Incentive Plan | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage on fair market value of common stock on the date of grant	100.00%
Award vesting period	4 years
Stock Options | 2011 Stock Incentive Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award grant period	10 years
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of award outstanding	4,309,000	4,231,000
Restricted Stock Units (RSUs) | 2011 and 2017 Stock Incentive Plan | Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock in settlement of employee tax withholding obligations	791,000	150,000	77,000
Performance-Based Restricted Stock Units (PSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Number of award outstanding	442,000	737,000
Stock Appreciation Rights
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	4 years
Award expiration period	10 years
Number of SAR exercised	20,000
Exercised fair value of SAR	$ 6.75
Number of award outstanding	200,000
Fair value of SAR	$ 1.79
Stock Appreciation Rights | Accrued Expenses And Other Current Liabilities
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of SAR liability	$ 358,000	$ 493,000

Stock-based Compensation - Assu

Stock-based Compensation - Assumptions Used in Black-Scholes Option Pricing Model (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days
Expected volatility, Minimum	37.70%	29.30%	28.80%
Expected volatility, Maximum	38.60%	31.90%	30.60%
Expected dividend yield	0.00%	0.00%	0.00%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	1.00%	0.40%	1.60%
Expected term (in years)			6 years 1 month 6 days
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	1.30%	0.70%	2.50%
Expected term (in years)			6 years 2 months 12 days

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Option Activity (Details) - 2017 Stock Incentive Plan - Stock Options - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning Balance	7,120
Number of Shares, Granted	151
Number of Shares, Exercised	(1,006)
Number of Shares, Forfeited	(346)
Number of Shares, Outstanding, Ending Balance	5,919	7,120
Number of Shares, Options exercisable at December 31, 2021	5,609
Number of Shares, Vested or expected to vest at December 31, 2021	5,900
Weighted-Average Exercise Price, Outstanding, Beginning Balance	$ 8.01
Weighted-Average Exercise Price, Granted	7.54
Weighted-Average Exercise Price, Exercised	2.25
Weighted-Average Exercise Price, Forfeited	10.66
Weighted-Average Exercise Price, Outstanding, Ending Balance	8.82	$ 8.01
Weighted-Average Exercise Price, Options exercisable at December 31, 2021	8.88
Weighted-Average Exercise Price, Vested or expected to vest at December 31, 2021	$ 8.83
Weighted-Average Remaining Contractual Term, Outstanding	4 years 4 months 9 days	4 years 10 months 17 days
Weighted-Average Remaining Contractual Term, Options exercisable at December 31, 2021	4 years 1 month 17 days
Weighted-Average Remaining Contractual Term, Vested or expected to vest at December 31, 2021	4 years 3 months 29 days
Aggregate Intrinsic Value, Outstanding	$ 4,205	$ 9,367
Aggregate Intrinsic Value, Options exercisable at December 31, 2021	4,059
Aggregate Intrinsic Value, Vested or expected to vest at December 31, 2021	$ 4,196

Stock-based Compensation - Su_2

Stock-based Compensation - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested, Beginning Balance | shares	4,231
Number of Shares, Granted | shares	1,705
Number of Shares, Vested | shares	(1,288)
Number of Shares, Forfeited | shares	(339)
Number of Shares, Unvested, Ending Balance | shares	4,309
Weighted-Average Grant Date Fair Value, Unvested, Beginning Balance | $ / shares	$ 5.43
Weighted-Average Grant Date Fair Value, Granted | $ / shares	8.18
Weighted-Average Grant Date Fair Value, Vested | $ / shares	6.12
Weighted-Average Grant Date Fair Value, Forfeited | $ / shares	5.01
Weighted-Average Grant Date Fair Value, Unvested, Ending Balance | $ / shares	$ 6.34
Aggregate Fair Value, Vested | $	$ 10,427

Stock-based Compensation - As_2

Stock-based Compensation - Assumptions of Estimated Based on Monte Carlo Simulation Model (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Performance-Based Restricted Stock Units (PSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	0.20%	1.20%
Volatility	78.60%	70.00%
Dividend yield	0.00%	0.00%
Cost of equity	12.00%	11.00%

Stock-based Compensation - Su_3

Stock-based Compensation - Summary of PSU Activity (Details) - Performance-Based Restricted Stock Units (PSUs) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested, Beginning Balance | shares	737
Number of Shares, Granted | shares	442
Number of Shares, Vested | shares	(737)
Number of Shares, Unvested, Ending Balance | shares	442
Weighted-Average Grant Date Fair Value, Unvested, Beginning Balance | $ / shares	$ 3.22
Weighted-Average Grant Date Fair Value, Granted | $ / shares	7.89
Weighted-Average Grant Date Fair Value, Vested | $ / shares	3.22
Weighted-Average Grant Date Fair Value, Unvested, Ending Balance | $ / shares	$ 7.89
Aggregate Fair Value, Vested | $	$ 6,449

Stock-based Compensation - Sche

Stock-based Compensation - Schedule of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 14,819	$ 13,155	$ 9,821
Product Cost of Revenue
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	137	153	216
Research and Development Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	2,665	2,447	1,569
Selling, General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 12,017	$ 10,555	$ 8,036

Stock-based Compensation - Su_4

Stock-based Compensation - Summary of Stock-based Compensation Expense Recognized in the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Change in fair value of SAR liability		$ 229	$ (1,123)
Recognized as additional paid-in capital	$ 14,819	12,926	10,944
Total stock-based compensation	$ 14,819	$ 13,155	$ 9,821

Net Income (Loss) per Share - S

Net Income (Loss) per Share - Schedule of Basic and Diluted Net Income (Loss) Per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net income (loss) attributable to common stockholders, basic and diluted	$ 3,207	$ 24,801	$ (48,206)
Weighted-average number of shares used to compute net income (loss) per share attributable to common stockholders:
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, basic	85,253	83,465	83,853
Dilutive effect of stock options	1,526	1,050
Dilutive effect of restricted stock units	2,078	763
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, diluted	88,857	85,278	83,853
Net income (loss) per share attributable to common stockholders:
Basic	$ 0.04	$ 0.30	$ (0.57)
Diluted	$ 0.04	$ 0.29	$ (0.57)

Net Income (Loss) per Share -_2

Net Income (Loss) per Share - Schedule of Potential Common Shares Excluded from the Computation of Diluted Net Income (Loss) Per Share Attributable to Common Stockholders (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from computation of diluted net income per share	3,411	4,119	4,641
Unvested Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from computation of diluted net income per share	712	1,030	1,516
Unvested Performance-Based Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from computation of diluted net income per share		983

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Summary of Disaggregation of Revenue Based on Geographic Locations Determined by Customer's Shipping Address (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Total revenue	$ 401,325	$ 393,246	$ 282,297
North America - United States
Disaggregation Of Revenue [Line Items]
Total revenue	154,765	127,217	103,451
North America - Canada
Disaggregation Of Revenue [Line Items]
Total revenue	66,537	38,960	36,466
North America
Disaggregation Of Revenue [Line Items]
Total revenue	221,302	166,177	139,917
Latin America
Disaggregation Of Revenue [Line Items]
Total revenue	27,841	34,926	24,043
Europe, Middle East and Africa
Disaggregation Of Revenue [Line Items]
Total revenue	30,378	35,933	38,154
Asia-Pacific - Australia
Disaggregation Of Revenue [Line Items]
Total revenue	89,548	116,661	42,218
Asia-Pacific - Other
Disaggregation Of Revenue [Line Items]
Total revenue	32,256	39,549	37,965
Asia-Pacific
Disaggregation Of Revenue [Line Items]
Total revenue	$ 121,804	$ 156,210	$ 80,183

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Summary of Disaggregation of Revenue Based on Geographic Locations Determined by Customer's Shipping Address (Parenthetical) (Details) - Other than United States and Australia	12 Months Ended
	Dec. 31, 2021Country
Disaggregation Of Revenue [Line Items]
Number of countries represents 10% or more of total revenue	0
Revenue | Geographic Concentration Risk
Disaggregation Of Revenue [Line Items]
Concentration risk percentage	10.00%

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Summary of Disaggregates of Revenue Based on Product Line (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Total revenue	$ 401,325	$ 393,246	$ 282,297
Product - Wireless
Disaggregation Of Revenue [Line Items]
Total revenue	170,233	111,255	58,234
Product - Fixed Telco
Disaggregation Of Revenue [Line Items]
Total revenue	66,017	96,904	38,734
Product - Cable
Disaggregation Of Revenue [Line Items]
Total revenue	117,692	137,924	144,409
Product
Disaggregation Of Revenue [Line Items]
Total revenue	353,942	346,083	241,377
Service - Wireless
Disaggregation Of Revenue [Line Items]
Total revenue	5,538	7,348	1,701
Service - Fixed Telco
Disaggregation Of Revenue [Line Items]
Total revenue	5,034	1,924	773
Service - Cable
Disaggregation Of Revenue [Line Items]
Total revenue	36,811	37,891	38,446
Service
Disaggregation Of Revenue [Line Items]
Total revenue	$ 47,383	$ 47,163	$ 40,920

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Revenue remaining performance obligation amount	$ 21,486
Prepaid Expenses and Other Current Assets
Disaggregation Of Revenue [Line Items]
Short-term capitalized contract costs	90	$ 95	$ 585
Other Assets
Disaggregation Of Revenue [Line Items]
Long-term capitalized contract costs	58	70	70
Deferred Revenue
Disaggregation Of Revenue [Line Items]
Revenue	15,402	23,048	22,273
Contract assets	95	771
Selling, General and Administrative Expenses
Disaggregation Of Revenue [Line Items]
Amortization of capitalized contract costs	$ 98	$ 568	$ 695

Revenue from Contracts with C_7

Revenue from Contracts with Customers - Additional Information (Details1)	Dec. 31, 2021
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Disaggregation Of Revenue [Line Items]
Revenue remaining performance obligation, percentage	67.00%
Revenue, remaining performance obligation, expected timing of satisfaction period	12 months
Minimum | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction period	2 years
Maximum | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Disaggregation Of Revenue [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction period	5 years

Segment Information - Additiona

Segment Information - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021Segment
Segment Reporting [Abstract]
Number of operating segments	1

Segment Information - Schedule

Segment Information - Schedule of Property and Equipment, Net by Location (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Property and equipment, net	$ 23,508	$ 28,880
United States
Segment Reporting Information [Line Items]
Property and equipment, net	17,089	20,988
China
Segment Reporting Information [Line Items]
Property and equipment, net	3,118	2,986
Australia
Segment Reporting Information [Line Items]
Property and equipment, net	2,027	2,849
Other
Segment Reporting Information [Line Items]
Property and equipment, net	$ 1,274	$ 2,057

Related Parties - Additional In

Related Parties - Additional Information (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted Stock Units (RSUs)
Related Party Transaction [Line Items]
Number of shares granted	1,705
Aggregate fair value vested	$ 10,427
Rongke Xie
Related Party Transaction [Line Items]
Compensation paid	$ 224	$ 187	$ 117
Rongke Xie | Restricted Stock Units (RSUs)
Related Party Transaction [Line Items]
Number of shares granted	116
Award vesting period	4 years
Aggregate fair value vested	$ 500
Selling, general and administrative expenses recognized	$ 110	$ 90	$ 46

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies Disclosure [Line Items]
Rent expense	$ 3,222,000	$ 3,252,000	$ 2,459,000
Deferred rent liability	151,000	90,000
Indemnification obligations material claims, outstanding	0	$ 0
Accrued contingency	$ 0
United States
Commitments And Contingencies Disclosure [Line Items]
Non-cancelable operating leases expiration year	2027
China
Commitments And Contingencies Disclosure [Line Items]
Non-cancelable operating leases expiration year	2027
Hong Kong
Commitments And Contingencies Disclosure [Line Items]
Non-cancelable operating leases expiration year	2027
Spain
Commitments And Contingencies Disclosure [Line Items]
Non-cancelable operating leases expiration year	2027
Australia
Commitments And Contingencies Disclosure [Line Items]
Non-cancelable operating leases expiration year	2027
Irish Subsidiary
Commitments And Contingencies Disclosure [Line Items]
Non-cancelable operating leases expiration year	2026

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Future Minimum Lease Payments under Non-cancelable Operating Leases (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments And Contingencies Disclosure [Abstract]
2022	$ 2,138
2023	2,028
2024	1,116
2025	874
2026	795
Thereafter	511
Total	$ 7,462

Employee Benefit Plan - Additio

Employee Benefit Plan - Additional Information (Details) - USD ($) $ in Thousands	Jan. 01, 2014	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Contribution Plan Disclosure [Line Items]
Percentage by which employer contribution matches up to 6% of employee's contribution	50.00%
Employer matching contributions made to plan		$ 1,615	$ 1,523	$ 1,762
Maximum
Defined Contribution Plan Disclosure [Line Items]
Percentage of employee's contributions eligible for employer contribution match	6.00%