| Standard label: | Unrealized Gain (Loss) on Hybrid Instrument, Net |
| Name: | us-gaap:UnrealizedGainLossOnHybridInstrumentNet |
| Documentation: | Amount of the unrealized gain (loss) in earnings for the period from the increase (decrease) in fair value on hybrid instruments measured at fair value. |
| 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:UnrealizedGainLossOnHybridInstrumentNet |
| Label | Role | Language |
| Unrealized Gain (Loss) on Hybrid Instrument, Net | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 815 15 50 1 | http://fasb.org/us-gaap/role/ref/legacyRef | 815 |
| FASB Accounting Standards Codification 825 10 50 30 (a) | http://fasb.org/us-gaap/role/ref/legacyRef | 825 |