v3.26.3
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical)
$ in Thousands
Jun. 30, 2026
USD ($)
$ / shares
shares
Dec. 31, 2025
USD ($)
$ / shares
shares
Accounts receivable allowance | $ $ 1,820 $ 2,889
Property, plant and equipment, accumulated depreciation | $ $ 76,391 67,372
Treasury stock (in shares) 254,232  
Class A Common Stock    
Common stock, shares authorized (in shares) 1,000,000,000  
Class B Common Stock    
Common stock, shares authorized (in shares) 500,000,000  
Common stock, shares outstanding (in shares) 31,891,652  
Customer relationships    
Intangible assets, accumulated amortization | $ $ 50,254 46,299
Other intangible assets    
Intangible assets, accumulated amortization | $ $ 58,920 49,731
HMH Holding BV And Subsidiaries [Member]    
Property, plant and equipment, accumulated depreciation | $   67,372
Intangible assets, accumulated amortization | $   $ (96,030)
Common stock, par value (in usd per share) | (per share)   $ 1
Common stock, shares authorized (in shares)   200
Common stock, shares issued (in shares)   200
Common stock, shares outstanding (in shares) 63,783,304 200
HMH Holding BV And Subsidiaries [Member] | Class A Common Stock    
Common stock, par value (in usd per share) | (per share) $ 0.01  
Common stock, shares authorized (in shares) 1,000,000,000  
Common stock, shares issued (in shares) 12,296,857  
Common stock, shares outstanding (in shares) 12,042,625 100
HMH Holding BV And Subsidiaries [Member] | Class B Common Stock    
Common stock, par value (in usd per share) | $ / shares $ 0.01  
Common stock, shares authorized (in shares) 500,000,000  
Common stock, shares issued (in shares) 31,891,652  
Common stock, shares outstanding (in shares) 31,891,652  
HMH Holding BV And Subsidiaries [Member] | Customer relationships    
Intangible assets, accumulated amortization | $   $ (46,299)
HMH Holding Inc. [Member]    
Common stock, par value (in usd per share) | $ / shares   $ 0.01
Common stock, shares authorized (in shares)   1,000
Common stock, shares issued (in shares)   1,000
Common stock, shares outstanding (in shares)   1,000
HMH Holding Inc. [Member] | Pro Forma [Member]    
Common stock, shares authorized (in shares)   200
Common stock, shares issued (in shares)   200
Common stock, shares outstanding (in shares)   200
HMH Holding Inc. [Member] | Pro Forma [Member] | Class A Common Stock    
Common stock, par value (in usd per share) | $ / shares   $ 0.01
Common stock, shares issued (in shares)   902,504
HMH Holding Inc. [Member] | Pro Forma [Member] | Class B Common Stock    
Common stock, par value (in usd per share) | $ / shares   $ 0.01