cm:Level3TextBlock: us-gaap:AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueTableTextBlock
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block] |
us-gaap:AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueTableTextBlock |
Tabular disclosure of fair value of investments in debt and equity securities in an unrealized loss position categorized neither as held-to-maturity nor trading securities. |
cm:Level3TextBlock |
Text Block (HTML) (nonnum:textBlockItemType) |
For Period (duration) |
(no balance type) |
false |
us-gaap:AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueTableTextBlock |