v3.21.1

Significant Accounting Policies (Tables) | 3 Months Ended
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Mar. 31, 2021
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 three months ended March 31, 2021 were typically as follows. All times are Eastern Standard Time:
Fund |  | Create/Redeem Cut-off* |  | NAV Calculation Time |  | NAV Calculation Date
Ultra Silver and UltraShort Silver |  | 1:00 p.m. |  | 1:25 p.m. |  | March 31, 2021
Ultra Gold and UltraShort Gold |  | 1:00 p.m. |  | 1:30 p.m. |  | March 31, 2021
Ultra Bloomberg Crude Oil, |  |  |  |  |  |
Ultra Bloomberg Natural Gas, |  |  |  |  |  |
UltraShort Bloomberg Crude Oil and |  |  |  |  |  |
UltraShort Bloomberg Natural Gas |  | 2:00 p.m. |  | 2:30 p.m. |  | March 31, 2021
Short Euro, |  |  |  |  |  |
Ultra Euro, |  |  |  |  |  |
Ultra Yen, |  |  |  |  |  |
UltraShort Australian Dollar, |  |  |  |  |  |
UltraShort Euro and |  |  |  |  |  |
UltraShort Yen |  | 3:00 p.m. |  | 4:00 p.m. |  | March 31, 2021
Short VIX Short-Term Futures ETF**, |  |  |  |  |  |
Ultra VIX Short-Term Futures ETF**, |  |  |  |  |  |
VIX Mid-Term Futures ETF** and |  |  |  |  |  |
VIX Short-Term Futures ETF** |  | 2:00 p.m. |  | 4:00 p.m. |  | March 31, 2021
* | 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 three months ended March 31, 2021.
** | On Monday, October 26, 2020 each Fund changed its NAV calculation time from 4:15 p.m. (Eastern Time) to 4:00 p.m. (Eastern Time). Please see Note 8 in these Notes to Financial Statements for more information.
Valuation of Investments using Fair Value Hierarchy | The following table summarizes the valuation of investments at March 31, 2021 using the fair value hierarchy:
|  | Level I - Quoted Prices |  |  | Level II - Other Significant Observable Inputs |  |  |  |
Fund |  | Short-Term U.S. Government and Agencies |  |  | Futures Contracts * |  |  | Foreign Currency Forward Contracts |  |  | Swap Agreements |  |  | Total |
ProShares Short Euro |  | $ | 999,973 |  |  | $ | 33,928 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,033,901 |
ProShares Short VIX Short-Term Futures ETF |  |  | 91,998,460 |  |  |  | 50,470,675 |  |  |  | — |  |  |  | — |  |  |  | 142,469,135 |
ProShares Ultra Bloomberg Crude Oil |  |  | 689,976,589 |  |  |  | 238,548,911 |  |  |  | — |  |  |  | (40,748,594 | ) |  |  | 887,776,906 |
ProShares Ultra Bloomberg Natural Gas |  |  | 33,999,110 |  |  |  | (11,300,062 | ) |  |  | — |  |  |  | — |  |  |  | 22,699,048 |
ProShares Ultra Euro |  |  | 999,973 |  |  |  | — |  |  |  | (222,404 | ) |  |  | — |  |  |  | 777,569 |
ProShares Ultra Gold |  |  | 86,998,893 |  |  |  | 393,125 |  |  |  | — |  |  |  | 6,160,430 |  |  |  | 93,552,448 |
ProShares Ultra Silver |  |  | 419,985,837 |  |  |  | (15,401,821 | ) |  |  | — |  |  |  | (28,421,003 | ) |  |  | 376,163,013 |
ProShares Ultra VIX Short-Term Futures ETF |  |  | 376,985,173 |  |  |  | (332,928,249 | ) |  |  | — |  |  |  | — |  |  |  | 44,056,924 |
ProShares Ultra Yen |  |  | 499,986 |  |  |  | — |  |  |  | (189,002 | ) |  |  | — |  |  |  | 310,984 |
ProShares UltraShort Australian Dollar |  |  | — |  |  |  | 67,102 |  |  |  | — |  |  |  | — |  |  |  | 67,102 |
ProShares UltraShort Bloomberg Crude Oil |  |  | 34,999,082 |  |  |  | (9,000,179 | ) |  |  | — |  |  |  | — |  |  |  | 25,998,903 |
ProShares UltraShort Bloomberg Natural Gas |  |  | 43,998,801 |  |  |  | 16,272,857 |  |  |  | — |  |  |  | — |  |  |  | 60,271,658 |
ProShares UltraShort Euro |  |  | 17,999,536 |  |  |  | — |  |  |  | 3,254,693 |  |  |  | — |  |  |  | 21,254,229 |
ProShares UltraShort Gold |  |  | 12,999,597 |  |  |  | 39,145 |  |  |  | — |  |  |  | (685,467 | ) |  |  | 12,353,275 |
ProShares UltraShort Silver |  |  | 14,999,620 |  |  |  | 3,276,894 |  |  |  | — |  |  |  | 771,233 |  |  |  | 19,047,747 |
ProShares UltraShort Yen |  |  | 14,499,635 |  |  |  | — |  |  |  | 2,335,922 |  |  |  | — |  |  |  | 16,835,557 |
ProShares VIX Mid-Term Futures ETF |  |  | 31,999,153 |  |  |  | (9,410,288 | ) |  |  | — |  |  |  | — |  |  |  | 22,588,865 |
ProShares VIX Short-Term Futures ETF |  |  | 152,996,232 |  |  |  | (59,803,004 | ) |  |  | — |  |  |  | — |  |  |  | 93,193,228 |
Total Trust |  | $ | 2,026,935,650 |  |  | $ | (128,740,966 | ) |  | $ | 5,179,209 |  |  | $ | (62,923,401 | ) |  | $ | 1,840,450,492 |
* | Includes cumulative appreciation (depreciation) of futures contracts as reported in the Schedule of Investments. Only current day’s variation margin is reported within the Statements of Financial Condition in receivable/payable on open futures.
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, 2020 using the fair value hierarchy:
|  | Level I - Quoted Prices |  |  | Level II - Other Significant Observable Inputs |  |  |  |
Fund |  | Short-Term U.S. Government and Agencies |  |  | Futures Contracts * |  |  | Foreign Currency Forward Contracts |  |  | Swap Agreements |  |  | Total |
ProShares Short Euro |  | $ | — |  |  | $ | (44,626 | ) |  | $ | — |  |  | $ | — |  |  | $ | (44,626 | )
ProShares Short VIX Short-Term Futures ETF |  |  | 69,999,639 |  |  |  | 8,348,783 |  |  |  | — |  |  |  | — |  |  |  | 78,348,422 |
ProShares Ultra Bloomberg Crude Oil |  |  | 219,998,394 |  |  |  | 144,564,039 |  |  |  | — |  |  |  | 18,242,195 |  |  |  | 382,804,628 |
ProShares Ultra Bloomberg Natural Gas |  |  | 29,999,889 |  |  |  | 6,500,721 |  |  |  | — |  |  |  | — |  |  |  | 36,500,610 |
ProShares Ultra Euro |  |  | — |  |  |  | — |  |  |  | 88,736 |  |  |  | — |  |  |  | 88,736 |
ProShares Ultra Gold |  |  | 74,999,467 |  |  |  | 2,646,874 |  |  |  | — |  |  |  | 5,140,980 |  |  |  | 82,787,321 |
ProShares Ultra Silver |  |  | 244,993,989 |  |  |  | 37,190,212 |  |  |  | — |  |  |  | 56,752,666 |  |  |  | 338,936,867 |
ProShares Ultra VIX Short-Term Futures ETF |  |  | 244,995,969 |  |  |  | (48,524,666 | ) |  |  | — |  |  |  | (24,807 | ) |  |  | 196,446,496 |
ProShares Ultra Yen |  |  | — |  |  |  | — |  |  |  | 67,087 |  |  |  | — |  |  |  | 67,087 |
ProShares UltraShort Australian Dollar |  |  | — |  |  |  | (138,950 | ) |  |  | — |  |  |  | — |  |  |  | (138,950 | )
ProShares UltraShort Bloomberg Crude Oil |  |  | — |  |  |  | (14,636,813 | ) |  |  | — |  |  |  | — |  |  |  | (14,636,813 | )
ProShares UltraShort Bloomberg Natural Gas |  |  | 9,999,861 |  |  |  | 379,310 |  |  |  | — |  |  |  | — |  |  |  | 10,379,171 |
ProShares UltraShort Euro |  |  | 9,999,861 |  |  |  | — |  |  |  | (1,136,704 | ) |  |  | — |  |  |  | 8,863,157 |
ProShares UltraShort Gold |  |  | — |  |  |  | (196,930 | ) |  |  | — |  |  |  | (268,728 | ) |  |  | (465,658 | )
ProShares UltraShort Silver |  |  | — |  |  |  | (220,076 | ) |  |  | — |  |  |  | (3,197,561 | ) |  |  | (3,417,637 | )
ProShares UltraShort Yen |  |  | — |  |  |  | — |  |  |  | (564,966 | ) |  |  | — |  |  |  | (564,966 | )
ProShares VIX Mid-Term Futures ETF |  |  | 44,999,732 |  |  |  | (1,133,616 | ) |  |  | — |  |  |  | — |  |  |  | 43,866,116 |
ProShares VIX Short-Term Futures ETF |  |  | 84,999,583 |  |  |  | (6,364,090 | ) |  |  | — |  |  |  | — |  |  |  | 78,635,493 |
Total Trust |  | $ | 1,034,986,384 |  |  | $ | 128,370,172 |  |  | $ | (1,545,847 | ) |  | $ | 76,644,745 |  |  | $ | 1,238,455,454 |
* | Includes cumulative appreciation (depreciation) of futures contracts as reported in the Schedule 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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