v3.10.0.1

Significant Accounting Policies (Tables) | 6 Months Ended
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Jun. 30, 2018
Accounting Policies [Abstract] |
Cut-off Times and Times of Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares | The cut-off times and the times of the calculation of the Funds’ final net asset value for creation and redemption of fund Shares for the six months ended June 30, 2018 were as follows. All times are Eastern Standard Time:
|  | Create/Redeem Cut-off* |  | NAV Calculation Time |  | NAV Calculation Date
UltraShort Silver, Ultra Silver |  | 6:30 a.m. |  | 7:00 a.m. |  | June 29, 2018
UltraShort Gold, Ultra Gold |  | 9:30 a.m. |  | 10:00 a.m. |  | June 29, 2018
UltraShort Bloomberg Crude Oil, Ultra Bloomberg Crude Oil |  | 2:00 p.m. |  | 2:30 p.m. |  | June 29, 2018
UltraPro 3x Short Crude Oil ETF, |  |  |  |  |  |
UltraPro 3x Crude Oil ETF |  |  |  |  |  |
UltraShort Bloomberg Natural Gas, Ultra Bloomberg Natural Gas |  | 2:00 p.m. |  | 2:30 p.m. |  | June 29, 2018
UltraShort Australian Dollar |  | 3:00 p.m. |  | 4:00 p.m. |  | June 29, 2018
Short Euro |  | 3:00 p.m. |  | 4:00 p.m. |  | June 29, 2018
UltraShort Euro, Ultra Euro |  |  |  |  |  |
UltraShort Yen, Ultra Yen |  | 3:00 p.m. |  | 4:00 p.m. |  | June 29, 2018
VIX Short-Term Futures ETF, Ultra VIX Short-Term Futures ETF, Short VIX Short-Term Futures ETF |  | 2:00 p.m. |  | 4:15 p.m. |  | June 29, 2018
VIX Mid-Term Futures ETF |  | 2:00 p.m. |  | 4:15 p.m. |  | June 29, 2018
* | Although the Funds’ shares may continue to trade on secondary markets subsequent to the calculation of the final NAV, these times represent the final opportunity to transact in creation or redemption units for the six months ended June 30, 2018.
Valuation of Investments using Fair Value Hierarchy | The following table summarizes the valuation of investments at June 30, 2018 using the fair value hierarchy:
|  | Level I - Quoted Prices |  |  | Level II - Other Significant Observable Inputs |  |  |  |
|  | Short-Term U.S. Government and Agencies |  |  | Futures Contracts* |  |  | Forward Agreements |  |  | Foreign Currency Forward Contracts |  |  | Swap Agreements |  |  | Total |
Short Euro |  | $ | 5,687,064 |  |  | $ | 87,213 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 5,774,277 |
Short VIX Short-Term Futures ETF |  |  | 92,995,995 |  |  |  | (22,528,398 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 70,467,597 |
Ultra Bloomberg Crude Oil |  |  | 365,955,628 |  |  |  | 17,289,103 |  |  |  | — |  |  |  | — |  |  |  | 82,428,870 |  |  |  | 465,673,601 |
Ultra Bloomberg Natural Gas |  |  | 17,960,426 |  |  |  | (118,623 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 17,841,803 |
Ultra Euro |  |  | 3,289,040 |  |  |  | — |  |  |  | — |  |  |  | (172,054 | ) |  |  | — |  |  |  | 3,116,986 |
Ultra Gold |  |  | 87,847,390 |  |  |  | (15,120 | ) |  |  | (7,152,896 | ) |  |  | — |  |  |  | — |  |  |  | 80,679,374 |
Ultra Silver |  |  | 212,508,884 |  |  |  | (7,970 | ) |  |  | (14,148,711 | ) |  |  | — |  |  |  | — |  |  |  | 198,352,203 |
Ultra VIX Short-Term Futures ETF |  |  | 42,998,148 |  |  |  | 39,797,429 |  |  |  | — |  |  |  | — |  |  |  | 264,480 |  |  |  | 83,060,057 |
Ultra Yen |  |  | 998,084 |  |  |  | — |  |  |  | — |  |  |  | (24,259 | ) |  |  | — |  |  |  | 973,825 |
UltraPro 3x Crude Oil ETF |  |  | — |  |  |  | 9,905,484 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 9,905,484 |
UltraPro 3x Short Crude Oil ETF |  |  | — |  |  |  | (5,442,454 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (5,442,454 | )
UltraShort Australian Dollar |  |  | 4,988,329 |  |  |  | 391,770 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 5,380,099 |
UltraShort Bloomberg Crude Oil |  |  | 173,652,213 |  |  |  | (7,161,949 | ) |  |  | — |  |  |  | — |  |  |  | (33,768,200 | ) |  |  | 132,722,064 |
UltraShort Bloomberg Natural Gas |  |  | 4,093,202 |  |  |  | 6,272 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 4,099,474 |
UltraShort Euro |  |  | 141,652,985 |  |  |  | — |  |  |  | — |  |  |  | 3,399,950 |  |  |  | — |  |  |  | 145,052,935 |
UltraShort Gold |  |  | 22,954,734 |  |  |  | 15,080 |  |  |  | 2,276,610 |  |  |  | — |  |  |  | — |  |  |  | 25,246,424 |
UltraShort Silver |  |  | 19,972,425 |  |  |  | 7,970 |  |  |  | 1,452,785 |  |  |  | — |  |  |  | — |  |  |  | 21,433,180 |
UltraShort Yen |  |  | 80,837,136 |  |  |  | — |  |  |  | — |  |  |  | 693,318 |  |  |  | — |  |  |  | 81,530,454 |
VIX Mid-Term Futures ETF |  |  | — |  |  |  | (378,240 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (378,240 | )
VIX Short-Term Futures ETF |  |  | 21,999,053 |  |  |  | 9,426,460 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 31,425,513 |
Total Trust |  | $ | 1,300,390,736 |  |  | $ | 41,274,027 |  |  | $ | (17,572,212 | ) |  | $ | 3,896,955 |  |  | $ | 48,925,150 |  |  | $ | 1,376,914,656 |
* | Includes cumulative appreciation/depreciation of futures contracts as reported in the Schedules of Investments. Only current day’s variation margin is reported within the Statements of Financial Condition in receivable/payable on open futures.
At June 30, 2018, there were no Level III portfolio investments for which significant unobservable inputs were used to determine fair value. The Funds’ policy is to recognize transfers between valuation levels at the end of the reporting period. At June 30, 2018, there were no significant transfers in or out of Level I and Level II fair value measurements. The inputs or methodology used for valuing investments are not necessarily an indication of the risk associated with investing in those securities. The following table summarizes the valuation of investments at December 31, 2017 using the fair value hierarchy:
|  | Level I - Quoted Prices |  |  | Level II - Other Significant Observable Inputs |  |  |  |
|  | Short-Term U.S. Government and Agencies |  |  | Futures Contracts* |  |  | Forward Agreements |  |  | Foreign Currency Forward Contracts |  |  | Swap Agreements |  |  | Total |
Short Euro |  | $ | 6,996,235 |  |  | $ | (166,288 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 6,829,947 |
Short VIX Short-Term Futures ETF |  |  | 494,910,644 |  |  |  | 17,041,449 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 511,952,093 |
Ultra Bloomberg Crude Oil |  |  | 459,515,902 |  |  |  | 11,945,979 |  |  |  | — |  |  |  | — |  |  |  | 62,238,361 |  |  |  | 533,700,242 |
Ultra Bloomberg Natural Gas |  |  | 50,961,356 |  |  |  | 7,225,810 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 58,187,166 |
Ultra Euro |  |  | 6,996,235 |  |  |  | — |  |  |  | — |  |  |  | 264,152 |  |  |  | — |  |  |  | 7,260,387 |
Ultra Gold |  |  | 88,884,844 |  |  |  | 5,480 |  |  |  | 3,646,355 |  |  |  | — |  |  |  | — |  |  |  | 92,536,679 |
Ultra Silver |  |  | 235,581,716 |  |  |  | 1,600 |  |  |  | 21,735,334 |  |  |  | — |  |  |  | — |  |  |  | 257,318,650 |
Ultra VIX Short-Term Futures ETF |  |  | 287,533,132 |  |  |  | (34,466,120 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 253,067,012 |
Ultra Yen |  |  | 1,997,933 |  |  |  | — |  |  |  | — |  |  |  | (34,824 | ) |  |  | — |  |  |  | 1,963,109 |
UltraPro 3x Crude Oil ETF |  |  | — |  |  |  | 1,417,998 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 1,417,998 |
UltraPro 3x Short Crude Oil ETF |  |  | — |  |  |  | (2,988,155 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (2,988,155 | )
UltraShort Australian Dollar |  |  | 11,983,904 |  |  |  | (893,220 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 11,090,684 |
UltraShort Bloomberg Crude Oil |  |  | 253,646,823 |  |  |  | (3,962,648 | ) |  |  | — |  |  |  | — |  |  |  | (30,607,142 | ) |  |  | 219,077,033 |
UltraShort Bloomberg Natural Gas |  |  | 3,999,751 |  |  |  | (1,097,049 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 2,902,702 |
UltraShort Euro |  |  | 204,770,166 |  |  |  | — |  |  |  | — |  |  |  | (6,344,269 | ) |  |  | — |  |  |  | 198,425,897 |
UltraShort Gold |  |  | 31,977,900 |  |  |  | (5,460 | ) |  |  | (1,488,259 | ) |  |  | — |  |  |  | — |  |  |  | 30,484,181 |
UltraShort Silver |  |  | 18,349,861 |  |  |  | (1,650 | ) |  |  | (1,716,163 | ) |  |  | — |  |  |  | — |  |  |  | 16,632,048 |
UltraShort Yen |  |  | 131,834,352 |  |  |  | — |  |  |  | — |  |  |  | 1,527,263 |  |  |  | — |  |  |  | 133,361,615 |
VIX Mid-Term Futures ETF |  |  | 20,993,515 |  |  |  | (2,215,280 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 18,778,235 |
VIX Short-Term Futures ETF |  |  | 134,845,604 |  |  |  | (4,761,877 | ) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 130,083,727 |
Total Trust |  | $ | 2,445,779,873 |  |  | $ | (12,919,431 | ) |  | $ | 22,177,267 |  |  | $ | (4,587,678 | ) |  | $ | 31,631,219 |  |  | $ | 2,482,081,250 |
* | Includes cumulative appreciation/depreciation of futures contracts as reported in the Schedules of Investments. Only current day’s variation margin is reported within the Statements of Financial Condition in receivable/payable on open futures.

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