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Summary of Significant Accounting Policies - Additional Information (Detail)
€ / shares in Units, € in Millions
 3 Months Ended 12 Months Ended
Oct. 01, 2024
USD ($)
Jun. 30, 2024
€ / shares
Mar. 31, 2024
USD ($)
Mar. 31, 2024
€ / shares
Dec. 31, 2023
USD ($)
€ / shares
Sep. 30, 2023
€ / shares
Jun. 30, 2023
€ / shares
Mar. 31, 2023
€ / shares
Dec. 31, 2024
USD ($)
IncentivePlan
shares
Dec. 31, 2024
EUR (€)
shares
Dec. 31, 2023
USD ($)
shares
Dec. 31, 2023
EUR (€)
shares
Dec. 31, 2022
USD ($)
Dec. 31, 2024
EUR (€)
IncentivePlan
Oct. 18, 2022
shares
Dec. 31, 2021
USD ($)
Summary Of Significant Accounting Policy [Line Items]                                
Cash, uninsured amount                 $ 74,000,000              
Percentage of guaranteed interest rate                 5.00%         5.00%    
Percentage of guaranteed interest rate plus a variable component                 3.37%         3.37%    
Aggregate exit compensation payments obligation including guaranteed interest                 $ 344,900,000         € 333.2    
Expire date of exit compensation                 Mar. 16, 2023 Mar. 16, 2023            
Annual recurring compensation obligation                 $ 9,300,000 € 8.9            
Accrued annual recurring compensation obligation                 $ 9,800,000   $ 10,100,000          
Number of shares tendered | shares                 831,000 831,000 67,000 67,000        
Exit compensation payments                 $ 17,400,000 € 15.7 $ 1,300,000 € 1.2        
Amount of redemptions                 17,400,000              
Total carrying value of assets held for sale                 11,901,000              
Impairment losses for long-lived assets and intangible assets                 0   0   $ 0      
Long-lived assets         $ 337,423,000       284,893,000   337,423,000          
Goodwill impairment $ 0               292,583,000   37,874,000   0      
Goodwill impairment charges, other                     0          
Impairment charges related to capitalized implementation costs                 $ 0   0   16,900,000      
Period of assurance-based warranty for product defects                 90 days to five years 90 days to five years            
Liability for warranty obligations         6,445,000       $ 4,512,000   6,445,000   7,196,000     $ 5,403,000
Number of stock incentive plans | IncentivePlan                 2         2    
Stock-based compensation expense                 $ 15,342,000   16,016,000   28,322,000      
Reduction of research and development expense recognized                 9,200,000   5,200,000   1,100,000      
Research and development costs                 221,463,000   258,311,000   173,757,000      
Network Solutions [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Long-lived assets                 358,600,000              
Goodwill impairment     $ 292,600,000                          
Services & Support [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Goodwill impairment                     37,900,000          
Purchase Agreement [Member] | Prior Factoring Agreement [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Credit agreement current borrowing capacity         14,300,000       $ 0   14,300,000          
ASU 2023-07 [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]                 true         true    
Change in Accounting Principle, Accounting Standards Update, Adoption Date                 Jan. 01, 2024         Jan. 01, 2024    
Prepaid Expenses and Other Current Assets [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Current deferred costs related to prepaid and other assets         2,100,000       $ 2,200,000   2,100,000          
Other Non-Current Assets [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Capitalized implementation costs         $ 300,000       100,000   300,000          
Selling, General and Administrative Expenses [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Amortization expense                 100,000   5,900,000   3,900,000      
Stock-based compensation expense                 $ 10,412,000   10,701,000   $ 20,844,000      
Wells Fargo Credit Agreement [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio                 0.0325 0.0325            
Wells Fargo Credit Agreement [Member] | Third and Fourth Quarters Ending Springing Covenant Event [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio                 0.035 0.035            
Wells Fargo Credit Agreement [Member] | First Quarter Ending Springing Covenant Period [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio                 0.04 0.04            
Wells Fargo Credit Agreement [Member] | Acorn HoldCo, Inc., [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Available for future borrowings                 $ 180,800,000              
Credit agreement current borrowing capacity                 $ 56,100,000              
Minimum [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Maintenance service periods                 1 month 1 month            
Maintenance contract period                 1 month 1 month            
Minimum [Member] | Building and Land Improvements [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 5 years         5 years    
Minimum [Member] | Office Machinery and Equipment [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 3 years         3 years    
Minimum [Member] | Engineering Machinery and Equipment [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 3 years         3 years    
Minimum [Member] | Computer Software [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 3 years         3 years    
Minimum [Member] | Wells Fargo Credit Agreement [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio                 0.035 0.035            
Fixed charge coverage ratio         0.0125       0.0125 0.0125            
Minimum [Member] | Wells Fargo Credit Agreement [Member] | Third and Fourth Quarters Ending Springing Covenant Event [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio                 0.035 0.035            
Maximum [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Maintenance service periods                 5 years 5 years            
Maintenance contract period                 5 years 5 years            
Maximum [Member] | Other Non-Current Assets [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Non-current deferred costs related to other non-current assets         $ 100,000       $ 100,000   $ 100,000          
Maximum [Member] | Building and Land Improvements [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 39 years         39 years    
Maximum [Member] | Office Machinery and Equipment [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 7 years         7 years    
Maximum [Member] | Engineering Machinery and Equipment [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 7 years         7 years    
Maximum [Member] | Computer Software [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Property, plant and equipment, estimated useful lives                 5 years         5 years    
Maximum [Member] | Wells Fargo Credit Agreement [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio         0.05       0.05 0.05            
Maximum [Member] | Wells Fargo Credit Agreement [Member] | First Quarter Ending Springing Covenant Period [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Net leverage ratio                 0.04 0.04            
Adtran Networks [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Number of shares tendered | shares                 831,000 831,000 67,000 67,000        
Exit compensation payments                 $ 17,400,000 € 15.7 $ 1,300,000 € 1.2        
Equity ownership percentage         34.70%       33.00%   34.70%     33.00%    
Annual recurring compensation payment per share | € / shares   € 0.52   € 0.52 $ 0.52 € 0.52 € 0.52 € 0.52                
Accrued liability per share | € / shares   € 0.59   € 0.59 $ 0.59 € 0.59 € 0.59 € 0.59                
Adtran Networks [Member] | Maximum [Member]                                
Summary Of Significant Accounting Policy [Line Items]                                
Number of additional shares authorized to purchase | shares                             15,346,544