v3.8.0.1

Statements of Financial Condition (Parenthetical) - USD ($) | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Short-term U.S. government and agency obligations, cost | $ 3,181,464,501 | $ 3,038,837,465
ProShares VIX Short-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 186,708,857 | 147,990,045
ProShares VIX Mid-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 35,953,365 | 45,486,489
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 770,073,989 | 170,391,741
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 521,285,333 | 434,676,067
ProShares UltraShort Bloomberg Crude Oil [Member] |  |
Short-term U.S. government and agency obligations, cost | 246,653,071 | 205,694,828
ProShares UltraShort Bloomberg Natural Gas [Member] |  |
Short-term U.S. government and agency obligations, cost | 2,998,485 | 2,899,188
ProShares UltraShort Gold [Member] |  |
Short-term U.S. government and agency obligations, cost | 34,939,314 | 60,540,275
ProShares UltraShort Silver [Member] |  |
Short-term U.S. government and agency obligations, cost | 17,965,709 | 21,549,766
ProShares Short Euro [Member] |  |
Short-term U.S. government and agency obligations, cost | 5,998,008 | 13,164,807
ProShares UltraShort Australian Dollar [Member] |  |
Short-term U.S. government and agency obligations, cost | 7,997,344 | 12,909,895
ProShares UltraShort Euro [Member] |  |
Short-term U.S. government and agency obligations, cost | 219,674,153 | 337,373,566
ProShares UltraShort Yen [Member] |  |
Short-term U.S. government and agency obligations, cost | 137,812,663 | 257,103,135
ProShares Ultra Bloomberg Crude Oil [Member] |  |
Short-term U.S. government and agency obligations, cost | 562,320,399 | 885,046,303
ProShares Ultra Bloomberg Natural Gas [Member] |  |
Short-term U.S. government and agency obligations, cost | 42,918,384 | 36,183,384
ProShares Ultra Gold [Member] |  |
Short-term U.S. government and agency obligations, cost | 101,893,747 | 95,356,703
ProShares Ultra Silver [Member] |  |
Short-term U.S. government and agency obligations, cost | 270,613,725 | 295,296,440
ProShares Ultra Euro [Member] |  |
Short-term U.S. government and agency obligations, cost | 10,995,458 | 11,891,729
ProShares Ultra Yen [Member] |  |
Short-term U.S. government and agency obligations, cost | $ 4,662,497 | $ 5,283,104

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