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Nature of Business - Additional Information (Detail)
€ in Millions
 3 Months Ended 12 Months Ended
Oct. 01, 2023
USD ($)
Jul. 18, 2022
USD ($)
Dec. 31, 2023
USD ($)
IncentivePlan
shares
Dec. 31, 2023
USD ($)
IncentivePlan
shares
Dec. 31, 2023
EUR (€)
shares
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2023
EUR (€)
IncentivePlan
shares
Oct. 18, 2022
shares
Dec. 31, 2020
USD ($)
Summary Of Significant Accounting Policy [Line Items]                    
Adjustment during period       $ (231,210,000)   $ (70,963,000) $ (6,305,000)      
Cash, uninsured amount     $ 83,200,000 $ 83,200,000            
Percentage of guaranteed interest rate     5.00% 5.00%       5.00%    
Percentage of guaranteed interest rate plus a variable component     3.12% 3.12%       3.12%    
Aggregate exit compensation payments obligation including guaranteed interest     $ 342,500,000 $ 342,500,000       € 310.3    
Expire date of exit compensation       Mar. 16, 2023 Mar. 16, 2023          
Annual recurring compensation obligation       $ 11,700,000 € 10.6          
Accrued annual recurring compensation obligation       $ 11,500,000            
Number of shares tendered | shares       67,000 67,000          
Exit compensation payments       $ 1,300,000 € 1.2          
Asset impairments           17,400,000        
Impairment losses of long-lived assets       0     0      
Impairment losses of intangible assets       0   0 0      
Goodwill impairment $ 0   0 37,874,000   0 0      
Impairment charges related to capitalized implementation costs       $ 0   16,900,000 0      
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 $ 6,445,000   7,196,000 5,403,000     $ 7,146,000
Non-current pension liability     $ 12,679,000 $ 12,679,000   10,624,000        
Number of stock incentive plans | IncentivePlan     2 2       2    
Goodwill     $ 353,415,000 $ 353,415,000   381,724,000        
Stock-based compensation expense       16,016,000   28,322,000 7,480,000      
Reduction of research and development expense recognized       5,200,000   1,100,000        
Research and development costs       258,311,000   173,757,000 108,663,000      
Effect on adoption of ASU     123,020,000 123,020,000   110,699,000        
Effect on adoption of ASU     87,706,000 87,706,000   66,998,000        
Tax benefit in other comprehensive (loss) income       (509,000)   1,966,000 1,596,000      
Cash and cash equivalents     87,167,000 87,167,000   108,644,000        
Wells Fargo Credit Agreement [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Covenant relief period, description   the period beginning upon the purchase by the Company of at least 60% of the outstanding shares of Adtran Networks not owned by the Company as of August 9, 2023 and the three consecutive quarterly test periods after such date                
Wells Fargo Credit Agreement [Member] | Credit Parties [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Cash and cash equivalents   $ 50,000,000                
Wells Fargo Credit Agreement [Member] | Company and Subsidiaries [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Cash and cash equivalents   75,000,000                
Wells Fargo Credit Agreement [Member] | Acorn HoldCo, Inc., [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Credit agreement maximum borrowing capacity   $ 400,000,000 400,000,000 400,000,000            
Available for future borrowings     202,700,000 202,700,000            
Credit agreement current borrowing capacity     38,800,000 38,800,000            
Services & Support [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Goodwill impairment       37,900,000            
Goodwill     $ 56,384,000 $ 56,384,000   83,444,000        
Adtran Networks [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Number of shares tendered | shares       67,000 67,000          
Exit compensation payments       $ 1,300,000 € 1.2          
Goodwill           $ 350,500,000        
Equity ownership percentage     34.70% 34.70%   34.70%   34.70%    
ASU 2021-08 [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]     true true       true    
Change in Accounting Principle, Accounting Standards Update, Adoption Date     Jul. 01, 2022 Jul. 01, 2022       Jul. 01, 2022    
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 $ 2,100,000   $ 1,500,000        
Other Non-Current Assets [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Capitalized implementation costs     $ 300,000 $ 300,000   6,200,000        
Minimum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Maintenance service periods       1 month 1 month          
Maintenance contract period       1 month 1 month          
Maximum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Operating lease, renewal term     1 year 1 year       1 year    
Maintenance service periods       5 years 5 years          
Maintenance contract period       5 years 5 years          
Maximum [Member] | Adtran Networks [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Number of additional shares authorized to purchase | shares     15,346,544 15,346,544       15,346,544 15,346,544  
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        
Building and Land Improvements [Member] | Minimum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     5 years 5 years       5 years    
Building and Land Improvements [Member] | Maximum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     39 years 39 years       39 years    
Office Machinery and Equipment [Member] | Minimum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     3 years 3 years       3 years    
Office Machinery and Equipment [Member] | Maximum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     7 years 7 years       7 years    
Engineering Machinery and Equipment [Member] | Minimum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     3 years 3 years       3 years    
Engineering Machinery and Equipment [Member] | Maximum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     7 years 7 years       7 years    
Computer Software [Member] | Minimum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     3 years 3 years       3 years    
Computer Software [Member] | Maximum [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Property, plant and equipment, estimated useful lives     5 years 5 years       5 years    
Selling, General and Administrative Expenses [Member]                    
Summary Of Significant Accounting Policy [Line Items]                    
Amortization expense       $ 5,900,000   3,900,000 1,000,000      
Stock-based compensation expense       $ 10,701,000   $ 20,844,000 $ 4,571,000