IndexOpen Option Contracts Written, Premiums
| Name | OpenOptionContractsWrittenPremiums |
|---|---|
| Namespace | http://fasb.org/us-gaap/2020-01-31 |
| Prefix | us-gaap |
| Data type | xbrli:monetaryItemType |
| Period type | instant |
| Substitution Group | xbrli:item |
| Balance | credit |
| Nillable | True |
| Abstract | False |
Labels
| Text | Lang | Role | Container role |
|---|---|---|---|
| Represents the premiums earned on the open option contracts held by the fund. This item is not required to be disclosed in Regulation S-X but is commonly reported by some funds. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Open Option Contracts Written, Premiums | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |