Summary of Significant Accounting Policies - Additional Information (Detail) € in Thousands, $ in Thousands		1 Months Ended		3 Months Ended
	Sep. 19, 2025 USD ($)	Apr. 30, 2026 USD ($)	Apr. 30, 2026 EUR (€)	Mar. 31, 2026 USD ($) shares	Mar. 31, 2026 EUR (€) shares	Mar. 31, 2025 USD ($) shares	Mar. 31, 2025 EUR (€) shares	Mar. 31, 2026 EUR (€)	Dec. 31, 2025 USD ($)	Oct. 18, 2022 shares
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				1.27%				1.27%
Aggregate exit compensation payments obligation including guaranteed interest				$ 351,700				€ 304,400
Expire date of exit compensation				Mar. 16, 2023	Mar. 16, 2023
Annual recurring compensation obligation				$ 9,000	€ 7,800	$ 9,000	€ 7,800
Accrued annual recurring compensation obligation				$ 2,200		$ 2,400
Number of shares tendered | shares				200,000	200,000
Cash and cash equivalents				$ 88,270					$ 95,696
3.75% Convertible Senior Notes Due 2030 [Member]
Summary Of Significant Accounting Policy [Line Items]
Principal amount of long term debt	$ 201,300
Debt instrument, interest rate, stated percentage	3.75%
Debt instrument, maturity date	Sep. 15, 2030
Net proceeds	$ 192,600
Wells Fargo Credit Agreement [Member]
Summary Of Significant Accounting Policy [Line Items]
Net leverage ratio						0.0325	0.0325
Wells Fargo Credit Agreement [Member] | Acorn HoldCo, Inc., [Member]
Summary Of Significant Accounting Policy [Line Items]
Available for future borrowings				319,200
Wells Fargo Credit Agreement Amendment [Member] | Credit Parties [Member]
Summary Of Significant Accounting Policy [Line Items]
Cash and cash equivalents				50,000
Wells Fargo Credit Agreement Amendment [Member] | Company and Subsidiaries [Member]
Summary Of Significant Accounting Policy [Line Items]
Cash and cash equivalents				$ 70,000
Maximum [Member] | Wells Fargo Credit Agreement [Member]
Summary Of Significant Accounting Policy [Line Items]
Net leverage ratio						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
Minimum [Member] | Wells Fargo Credit Agreement [Member]
Summary Of Significant Accounting Policy [Line Items]
Fixed charge coverage ratio						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
Adtran Networks [Member]
Summary Of Significant Accounting Policy [Line Items]
Number of shares tendered | shares				200,000	200,000
Exit compensation payments						$ 13	€ 12
Adtran Networks [Member] | Subsequent Event [Member]
Summary Of Significant Accounting Policy [Line Items]
Exit compensation payments		$ 4,100	€ 3,600
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	1,000	1,000