cm:Concept: us-gaap:InventoryRealEstateLandAndLandDevelopmentCosts
| Inventory, Real Estate, Land and Land Development Costs |
| us-gaap:InventoryRealEstateLandAndLandDevelopmentCosts |
| Carrying amount as of the balance sheet date, net of valuation allowances and impairment losses, of costs of land expected to be developed in the near term plus capitalized costs of development, for purposes of selling completed units to home buyers or commercial or industrial entities.. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:InventoryRealEstateLandAndLandDevelopmentCosts |