CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Long Duration Contracts Assumptions By Product And Guarantee [Line Items] | |||
| Brokerage commissions | $ 22,207 | $ 19,025 | $ 4,643 |
| Brokerage commissions as a percentage of average daily net assets | 0.02% | 0.03% | 0.01% |
| Rebalancing Investments Transaction [Member] | |||
| Long Duration Contracts Assumptions By Product And Guarantee [Line Items] | |||
| Brokerage commissions | $ 17,872 | $ 11,997 | $ 3,665 |
| Brokerage commissions as a percentage of average daily net assets | 80.48% | 63.06% | 78.94% |
| Trades Necessitated By Creation And Redemption Activity [Member] | |||
| Long Duration Contracts Assumptions By Product And Guarantee [Line Items] | |||
| Brokerage commissions | $ 4,335 | $ 7,028 | $ 978 |
| Brokerage commissions as a percentage of average daily net assets | 19.52% | 36.94% | 21.06% |