| Standard label: | Increase (Decrease) in Marketable Securities, Restricted | 
| Name: | us-gaap:IncreaseDecreaseInMarketableSecuritiesRestricted | 
| Documentation: | The change during the period, either increase or decrease, in total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral. | 
| Object type: | cm:Concept | 
| Data type: | Monetary (xbrli:monetaryItemType) | 
| Period type: | For Period (duration) | 
| Balance type: | Credit | 
| Abstract: | false | 
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:IncreaseDecreaseInMarketableSecuritiesRestricted | 
| Label | Role | Language | 
| Increase (Decrease) in Marketable Securities, Restricted | http://www.xbrl.org/2003/role/label | en-US | 
| Reference | Role | Topic | 
| FASB Accounting Standards Codification 235 10 S99 1 (SX 210.4-08(b)) | http://fasb.org/us-gaap/role/ref/legacyRef | 235 | 
| Part Of Roll Up: | 
| us-gaap:IncreaseDecreaseInRestrictedCashAndInvestmentsForOperatingActivities |