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Summary of Significant Accounting Policies - Additional Information (Detail) € in Thousands, $ in Thousands |  | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Apr. 14, 2025 USD ($) shares | Apr. 14, 2025 EUR (€) shares | Mar. 31, 2025 USD ($) shares | Mar. 31, 2025 EUR (€) shares | Mar. 31, 2024 USD ($) shares | Mar. 31, 2024 EUR (€) shares | Mar. 31, 2025 EUR (€) | Dec. 31, 2024 USD ($) | 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 |  |  |  | 2.27% |  |  |  | 2.27% |  |
Aggregate exit compensation payments obligation including guaranteed interest |  |  |  | $ 366,100 |  |  |  | € 338,500 |  |
Expire date of exit compensation |  |  |  | Mar. 16, 2023 | Mar. 16, 2023 |  |  |  |  |
Annual recurring compensation obligation |  |  |  | $ 9,700 | € 8,900 |  |  |  |  |
Accrued annual recurring compensation obligation |  |  |  | 2,400 |  | $ 2,500 |  |  |  |
Exit compensation payments |  |  |  | 13 | € 12 | 5 | € 4 |  |  |
Cash and cash equivalents |  |  |  | 101,321 |  | 106,757 |  |  | $ 76,021 |
Less: Net Income attributable to non-controlling interest | [1] |  |  | $ 2,319 |  | 2,530 |  |  |  |
Revision [Member] |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |  |  |  |  |  |  |
Less: Net Income attributable to non-controlling interest |  |  |  |  |  | (350) |  |  |  |
Previously Reported [Member] |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  |  |  | 106,757 |  |  |  |
Less: Net Income attributable to non-controlling interest |  |  |  |  |  | 2,880 |  |  |  |
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 |  |  |  | $ 180,700 |  |  |  |  |  |
Credit agreement current borrowing capacity |  |  |  | $ 25,800 |  |  |  |  |  |
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] |  |  |  |  |  |  |  |  |  |
Exit compensation payments |  |  |  | $ 13 | € 12 | $ 5 | € 4 |  |  |
Equity ownership percentage |  |  |  | 33.00% |  |  |  | 33.00% | 33.00% |
Adtran Networks [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policy [Line Items] |  |  |  |  |  |  |  |  |  |
Number of shares tendered | shares |  | 400,000 | 400,000 |  |  |  |  |  |  |
Exit compensation payments |  | $ 7,500 | € 7,000 |  |  |  |  |  |  |
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 |  |  |
[1] | For the three months ended March 31, 2025, we accrued $2.4 million net income attributable to non-controlling interest, representing the recurring cash compensation earned by non-controlling interest shareholders post-DPLTA. For the three months ended March 31, 2024, we recognized $2.5 million of net gain attributable to non-controlling interest, representing the recurring cash compensation earned by non-controlling interest shareholders post DPTLA.

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