Income taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | 12 Months Ended | |||||
|---|---|---|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Effective Income Tax Rate Reconciliation [Line Items] | ||||||||
| Income before income taxes | $ (9,525) | $ 14,926 | $ 202 | $ 26,060 | ||||
| Income tax expense | $ (4,506) | $ 5,158 | $ 1,346 | 10,414 | ||||
| HMH Holding BV And Subsidiaries [Member] | ||||||||
| Effective Income Tax Rate Reconciliation [Line Items] | ||||||||
| Income before income taxes | $ 72,590 | $ 72,590 | $ 76,489 | |||||
| Statutory income tax rate (25.8%) | (18,728) | (19,734) | ||||||
| Difference between local income tax rate and Dutch income tax rate | 2,506 | 2,783 | ||||||
| Nondeductible expenses | (8,588) | (6,812) | ||||||
| Unrecognized tax benefits | (352) | (1,560) | ||||||
| Income taxed to U.S. shareholders | [1] | 6,640 | 7,612 | |||||
| Shareholder tax benefit | (227) | (1,660) | ||||||
| Change in valuation allowance | (2,670) | (2,502) | ||||||
| Change in tax rate | (356) | 0 | ||||||
| Withholding taxes | (4,289) | (2,356) | ||||||
| Other | (403) | (304) | ||||||
| Income tax expense | $ 26,467 | $ 24,533 | ||||||
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- Definition Effective income tax rate reconciliation unrecognized tax benefits amount. No definition available.
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- Definition Effective income tax rate reconciliation withholding taxes amount. No definition available.
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- Definition Amount of reported income tax expense (benefit) from difference to expected income tax expense (benefit) computed by applying statutory federal (national) income tax rate to pretax income (loss) from continuing operation, attributable to cross-border tax law. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying statutory federal (national) tax rate to pretax income (loss) from continuing operation attributable to other reconciling item. Excludes state and local income tax expense (benefit), federal tax expense (benefit), statutory income tax expense (benefit) outside of country of domicile, tax credit, nondeductible expense, deduction, income tax settlement, income tax contingency, and cross-border tax law. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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