{"cik":2021880,"taxonomy":"us-gaap","tag":"OperatingLeaseRightOfUseAsset","label":"Operating Lease, Right-of-Use Asset","description":"Amount of lessee's right to use underlying asset under operating lease.","entityName":"HMH Holding Inc","units":{"USD":[{"end":"2025-12-31","val":48739000,"accn":"0001628280-26-053385","fy":2026,"fp":"Q2","form":"10-Q","filed":"2026-08-05","frame":"CY2025Q4I"},{"end":"2026-06-30","val":45834000,"accn":"0001628280-26-053385","fy":2026,"fp":"Q2","form":"10-Q","filed":"2026-08-05","frame":"CY2026Q2I"}]}}