| Standard label: | Guarantees, Fair Value Disclosure |
| Name: | us-gaap:GuaranteesFairValueDisclosure |
| Documentation: | Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Credit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:GuaranteesFairValueDisclosure |
| Label | Role | Language |
| Guarantees, Fair Value Disclosure | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 460 10 50 5 (a) | http://fasb.org/us-gaap/role/ref/legacyRef | 460 |
| Part Of Roll Up: |
| us-gaap:FinancialLiabilitiesFairValueDisclosure |