| Standard label: | Proceeds from (Repurchase of) Trust Preferred Securities | 
| Name: | us-gaap:ProceedsFromRepurchaseOfTrustPreferredSecurities | 
| Documentation: | The cash inflow from issuance of trust preferred securities, net of the cash outflow for repurchasing trust preferred securities, by a business trust or other special purpose entity, mainly established by a bank holding entity, to third party investors. The trust's assets are deeply subordinated debentures of the bank holding entity. Most trust preferred securities are subject to a mandatory redemption upon the repayment of the debentures. | 
| 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:ProceedsFromRepurchaseOfTrustPreferredSecurities | 
| Label | Role | Language | 
| Proceeds from (Repurchase of) Trust Preferred Securities | http://www.xbrl.org/2003/role/label | en-US | 
| Proceeds from (Repurchase of) Trust Preferred Securities, Total | http://www.xbrl.org/2003/role/totalLabel | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 235 10 S99 3 (SX 210.12-04(a)) | http://www.xbrl.org/2009/role/commonPracticeRef | 235 | 
| Part Of Roll Up: | 
| us-gaap:NetCashProvidedByUsedInFinancingActivitiesContinuingOperations |