| Standard label: | Proceeds from Collection of Loans Held-for-sale | 
| Name: | us-gaap:ProceedsFromCollectionOfLoansHeldForSale | 
| Documentation: | The cash inflow from collection of repayments from borrowers on loans that are held with the intention to resell in the near future; includes mortgages and other types of loans. | 
| Object type: | cm:Concept | 
| Data type: | Monetary (xbrli:monetaryItemType) | 
| Period type: | For Period (duration) | 
| Balance type: | Debit | 
| Abstract: | false | 
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:ProceedsFromCollectionOfLoansHeldForSale | 
| Label | Role | Language | 
| Proceeds from Collection of Loans Held-for-sale | http://www.xbrl.org/2003/role/label | en-US | 
| Proceeds from Collection of Loans Held-for-sale, Total | http://www.xbrl.org/2003/role/totalLabel | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 230 10 45 16 (a) | http://www.xbrl.org/2009/role/commonPracticeRef | 230 | 
| FASB Accounting Standards Codification 230 10 45 21 | http://www.xbrl.org/2009/role/commonPracticeRef | 230 | 
| Part Of Roll Up: | 
| us-gaap:ProceedsFromSaleAndCollectionOfLoansHeldforsale |