cm:Concept: us-gaap:InterestIncomeFederalFundsSold
| Interest Income, Federal Funds Sold |
| us-gaap:InterestIncomeFederalFundsSold |
| Interest income on federal funds sold. Federal funds sold represent the excess federal funds held by one commercial bank which it lends to another commercial bank, usually at an agreed-upon (federal funds) rate of interest. Such loans generally are of short-duration (overnight). |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:InterestIncomeFederalFundsSold |