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- Definition

Subsidiary, Voting Power Percentage

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No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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No definition available.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480070/505-10-S50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480100/505-10-S45-3

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480100/505-10-S45-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Name Accounting Standards Codification
-Section S45
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Name Accounting Standards Codification
-Section S50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-11

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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Basis of presentation and description of the transactions - Additional Information (Details) - $ / shares			12 Months Ended
	May 05, 2026	Apr. 02, 2026	Dec. 31, 2025
Common Class A [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock Repurchased During Period, Shares		2,100,000
Stock Repurchased and Retired During Period, Shares	685,844	2,100,000
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture		836,781
Common Class B [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock Repurchased During Period, Shares		2,100,000
Stock Repurchased and Retired During Period, Shares	685,844	2,100,000
HMH Holding Inc. [Member] \| Pro Forma [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Subsidiary, Voting Power Percentage			100.00%
HMH Holding Inc. [Member] \| Pro Forma [Member] \| Company and Non controlling Interests [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Equity interest percentage			24.40%
HMH Holding Inc. [Member] \| Pro Forma [Member] \| Common Class A [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture			902,504
IPO [Member] \| HMH Holding Inc. [Member] \| Pro Forma [Member] \| Common Class A [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Sale of Stock, Price Per Share			$ 20
Stock Repurchased During Period, Shares			10,520,000
IPO [Member] \| HMH Holding Inc. [Member] \| Pro Forma [Member] \| Common Class B [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock Repurchased During Period, Shares			10,520,000
Underwriters [Member] \| HMH Holding Inc. [Member] \| Pro Forma [Member] \| Common Class A [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock Repurchased and Retired During Period, Shares			1,578,000
Underwriters [Member] \| HMH Holding Inc. [Member] \| Pro Forma [Member] \| Common Class B [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock Repurchased and Retired During Period, Shares			1,578,000