| Standard label: | Available-for-sale Securities and Held-to-maturity Securities |
| Name: | us-gaap:AvailableForSaleSecuritiesAndHeldToMaturitySecurities |
| Documentation: | Amount of debt and equity financial instruments classified as either held-to-maturity or available-for-sale. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:AvailableForSaleSecuritiesAndHeldToMaturitySecurities |
| Label | Role | Language |
| Available-for-sale Securities and Held-to-maturity Securities | http://www.xbrl.org/2003/role/label | en-US |
| Available-for-sale Securities and Held-to-maturity Securities, Total | http://www.xbrl.org/2003/role/totalLabel | en-US |
| Reference | Role | Topic |