cm:Level3TextBlock: us-gaap:NetInvestmentInLeaseCreditQualityIndicatorTableTextBlock
| Net Investment in Lease, Credit Quality Indicator [Table Text Block] |
| us-gaap:NetInvestmentInLeaseCreditQualityIndicatorTableTextBlock |
| Tabular disclosure of credit quality indicator for net investment in sales-type and direct financing leases. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:NetInvestmentInLeaseCreditQualityIndicatorTableTextBlock |