Restructuring and other expenses.

No definition available.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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- Definition

Amount of loss from impairment of right-of-use asset from operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 440
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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

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- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
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Commitments and Contingencies - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026 USD ($) Employee	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	195
Restructuring and other expenses (income), net		$ 5,004	$ 1,072	$ 5,004	$ 4,343
Impairment of right-of-use assets			$ 700		$ 1,800
HMH Holding BV And Subsidiaries [Member]
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	135
Restructuring and other expenses (income), net						$ 4,631	$ (301)
Impairment of right-of-use assets						1,800
Outstanding bank guarantees						5,000
Purchase commitments						88,000
Restructuring and other expenses						4,600	$ 0
Bank guarantee
Restructuring Cost and Reserve [Line Items]
Outstanding bank guarantees	$ 30,100	$ 30,100		$ 30,100
Bank guarantee \| HMH Holding BV And Subsidiaries [Member]
Restructuring Cost and Reserve [Line Items]
Outstanding bank guarantees						$ 30,900
Norway
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	110
Norway \| HMH Holding BV And Subsidiaries [Member]
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	110
Mexico
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	60
Germany
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	25
Germany \| HMH Holding BV And Subsidiaries [Member]
Restructuring Cost and Reserve [Line Items]
Number of employees impacted by restructuring plan \| Employee	25