cm:Level2TextBlock: us-gaap:RevenueRecognitionRetailLandSales
| Revenue Recognition, Retail Land Sales [Policy Text Block] |
| us-gaap:RevenueRecognitionRetailLandSales |
| Disclosure of accounting policy for the timing and amount of revenue recognized on retail sales of real estate. The entity also may disclose its treatment of any unearned or deferred revenue that arises from the transaction. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:RevenueRecognitionRetailLandSales |