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Offering Costs (Detail)
|
3 Months Ended |
|---|---|
|
Mar. 31, 2013
M
|
|
| Organization And Offering Costs [Line Items] | |
| Offering costs, amortization period, months | 12 |
| Sponsor reimbursement of offering costs, maximum for each Leveraged Fund | 0.85% |
|
New Fund [Member]
|
|
| Organization And Offering Costs [Line Items] | |
| Sponsor reimbursement of offering costs, maximum for each Leveraged Fund | 0.95% |