cm:Level1TextBlock: us-gaap:CashCashEquivalentsAndMarketableSecuritiesTextBlock
| Cash, Cash Equivalents, and Marketable Securities [Text Block] |
| us-gaap:CashCashEquivalentsAndMarketableSecuritiesTextBlock |
| The entire disclosure of cash, cash equivalents, and debt and equity securities, including any unrealized or realized gain (loss). |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:CashCashEquivalentsAndMarketableSecuritiesTextBlock |
| CashCashEquivalentsAndMarketableSecuritiesDisclosure |