| Standard label: | Proceeds from Sale of Available-for-sale Securities | 
| Name: | us-gaap:ProceedsFromSaleOfAvailableForSaleSecurities | 
| Documentation: | The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities. | 
| 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:ProceedsFromSaleOfAvailableForSaleSecurities | 
| Label | Role | Language | 
| Proceeds from Sale of Available-for-sale Securities | http://www.xbrl.org/2003/role/label | en-US | 
| Proceeds from Sale of Available-for-sale Securities, Total | http://www.xbrl.org/2003/role/totalLabel | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 230 10 45 12 (a),(b) | http://fasb.org/us-gaap/role/ref/legacyRef | 230 | 
| FASB Accounting Standards Codification 320 10 45 11 | http://fasb.org/us-gaap/role/ref/legacyRef | 320 |