IndexOpen Option Contracts Written, Number of Contracts
| Name | OpenOptionContractsWrittenNumberOfContracts |
|---|---|
| Namespace | http://fasb.org/us-gaap/2020-01-31 |
| Prefix | us-gaap |
| Data type | xbrli:decimalItemType |
| Period type | instant |
| Substitution Group | xbrli:item |
| Balance | None |
| Nillable | True |
| Abstract | False |
Labels
| Text | Lang | Role | Container role |
|---|---|---|---|
| Open Option Contracts Written, Number of Contracts | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
Related Parent Concepts
| Name | Relation Type | Role | |
|---|---|---|---|
 | us-gaap:OpenOptionContractsWrittenLineItems | parent-child | http://fasb.org/us-gaap/role/disclosure/OpenOptionContractsWritten |
| us-gaap:OpenOptionContractsWrittenLineItems | domain-member | http://fasb.org/us-gaap/role/disclosure/OpenOptionContractsWritten |