| Standard label: | Withdrawal from Contract Holders Funds |
| Name: | us-gaap:WithdrawalFromContractHoldersFunds |
| Documentation: | The cash outflow for a segregated fund account during the period. |
| 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:WithdrawalFromContractHoldersFunds |
| Label | Role | Language |
| Withdrawal from Contract Holders Funds | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 230 10 45 15 | http://fasb.org/us-gaap/role/ref/legacyRef | 230 |
| Part Of Roll Up: |
| us-gaap:NetChangeContractHoldersFunds |