| Standard label: | Gain (Loss) on Price Risk Fair Value Hedge Ineffectiveness |
| Name: | us-gaap:GainLossOnPriceRiskFairValueHedgeIneffectiveness |
| Documentation: | The net gain (loss) recognized in earnings during the reporting period due to the ineffectiveness of price risk fair value hedges. |
| 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:GainLossOnPriceRiskFairValueHedgeIneffectiveness |
| Label | Role | Language |
| Gain (Loss) on Price Risk Fair Value Hedge Ineffectiveness | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 815 25 50 1 (a)(1) | http://fasb.org/us-gaap/role/ref/legacyRef | 815 |