Summary of Significant Accounting Policies - Additional Information (Detail) € in Thousands, $ in Thousands	3 Months Ended				12 Months Ended
	Mar. 31, 2024 USD ($) shares	Mar. 31, 2024 EUR (€) shares	Mar. 31, 2023 USD ($) shares	Mar. 31, 2023 EUR (€) shares	Dec. 31, 2023 USD ($)	Mar. 31, 2024 EUR (€)	Oct. 18, 2022 shares	Jul. 18, 2022 USD ($)
Summary Of Significant Accounting Policy [Line Items]
Percentage of guaranteed interest rate	5.00%					5.00%
Percentage of guaranteed interest rate plus a variable component	3.62%					3.62%
Aggregate exit compensation payments obligation including guaranteed interest	$ 365,700					€ 338,900
Expire date of exit compensation	Mar. 16, 2023	Mar. 16, 2023
Annual recurring compensation obligation	$ 11,500	€ 10,600			$ 11,500
Accrued annual recurring compensation obligation	$ 2,900		$ 2,800		11,500
Number of shares tendered | shares	1,000	1,000	62,000	62,000
Exit compensation payments	$ 5	€ 4	$ 1,200	€ 1,100
Cash and cash equivalents	$ 106,757				$ 87,167
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	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
Wells Fargo Credit Agreement [Member] | Company and Subsidiaries [Member]
Summary Of Significant Accounting Policy [Line Items]
Cash and cash equivalents								$ 75,000
Wells Fargo Credit Agreement [Member] | Acorn HoldCo, Inc., [Member]
Summary Of Significant Accounting Policy [Line Items]
Available for future borrowings	$ 203,000
Credit agreement current borrowing capacity	22,700
Adtran Networks [Member]
Summary Of Significant Accounting Policy [Line Items]
Number of shares tendered | shares			62,000	62,000
Exit compensation payments	$ 5	€ 4	$ 1,200	€ 1,100
Equity ownership percentage	34.70%				34.70%	34.70%
Adtran Networks [Member] | Maximum [Member]
Summary Of Significant Accounting Policy [Line Items]
Number of additional shares authorized to purchase | shares							15,346,544
Number of shares tendered | shares	1,000	1,000