v3.21.1

Significant Accounting Policies - Valuation of Investments using Fair Value Hierarchy (Detail) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | $ 1,840,450,492 | $ 1,238,455,454
ProShares Short Euro [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 1,033,901 | (44,626)
ProShares Short VIX Short-Term Futures ETF [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 142,469,135 | 78,348,422
ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 887,776,906 | 382,804,628
ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 22,699,048 | 36,500,610
ProShares Ultra Euro [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 777,569 | 88,736
ProShares Ultra Gold [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 93,552,448 | 82,787,321
ProShares Ultra Silver [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 376,163,013 | 338,936,867
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 44,056,924 | 196,446,496
ProShares Ultra Yen [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 310,984 | 67,087
ProShares UltraShort Australian Dollar [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 67,102 | (138,950)
ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 25,998,903 | (14,636,813)
ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 60,271,658 | 10,379,171
ProShares UltraShort Euro [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 21,254,229 | 8,863,157
ProShares UltraShort Gold [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 12,353,275 | (465,658)
ProShares UltraShort Silver [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 19,047,747 | (3,417,637)
ProShares UltraShort Yen [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 16,835,557 | (564,966)
ProShares VIX Mid-Term Futures ETF [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 22,588,865 | 43,866,116
ProShares VIX Short-Term Futures ETF [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 93,193,228 | 78,635,493
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 2,026,935,650 | 1,034,986,384
Level I - Quoted Prices [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (128,740,966) | 128,370,172
Level I - Quoted Prices [Member] | ProShares Short Euro [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 999,973 |
Level I - Quoted Prices [Member] | ProShares Short Euro [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 33,928 | (44,626)
Level I - Quoted Prices [Member] | ProShares Short VIX Short-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 91,998,460 | 69,999,639
Level I - Quoted Prices [Member] | ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 50,470,675 | 8,348,783
Level I - Quoted Prices [Member] | ProShares Ultra Bloomberg Crude Oil [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 689,976,589 | 219,998,394
Level I - Quoted Prices [Member] | ProShares Ultra Bloomberg Crude Oil [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 238,548,911 | 144,564,039
Level I - Quoted Prices [Member] | ProShares Ultra Bloomberg Natural Gas [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 33,999,110 | 29,999,889
Level I - Quoted Prices [Member] | ProShares Ultra Bloomberg Natural Gas [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (11,300,062) | 6,500,721
Level I - Quoted Prices [Member] | ProShares Ultra Euro [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 999,973 |
Level I - Quoted Prices [Member] | ProShares Ultra Gold [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 86,998,893 | 74,999,467
Level I - Quoted Prices [Member] | ProShares Ultra Gold [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 393,125 | 2,646,874
Level I - Quoted Prices [Member] | ProShares Ultra Silver [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 419,985,837 | 244,993,989
Level I - Quoted Prices [Member] | ProShares Ultra Silver [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (15,401,821) | 37,190,212
Level I - Quoted Prices [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 376,985,173 | 244,995,969
Level I - Quoted Prices [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (332,928,249) | (48,524,666)
Level I - Quoted Prices [Member] | ProShares Ultra Yen [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 499,986 |
Level I - Quoted Prices [Member] | ProShares UltraShort Australian Dollar [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 67,102 | (138,950)
Level I - Quoted Prices [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 34,999,082 |
Level I - Quoted Prices [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (9,000,179) | (14,636,813)
Level I - Quoted Prices [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 43,998,801 | 9,999,861
Level I - Quoted Prices [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 16,272,857 | 379,310
Level I - Quoted Prices [Member] | ProShares UltraShort Euro [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 17,999,536 | 9,999,861
Level I - Quoted Prices [Member] | ProShares UltraShort Gold [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 12,999,597 |
Level I - Quoted Prices [Member] | ProShares UltraShort Gold [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 39,145 | (196,930)
Level I - Quoted Prices [Member] | ProShares UltraShort Silver [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 14,999,620 |
Level I - Quoted Prices [Member] | ProShares UltraShort Silver [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | 3,276,894 | (220,076)
Level I - Quoted Prices [Member] | ProShares UltraShort Yen [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 14,499,635 |
Level I - Quoted Prices [Member] | ProShares VIX Mid-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 31,999,153 | 44,999,732
Level I - Quoted Prices [Member] | ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (9,410,288) | (1,133,616)
Level I - Quoted Prices [Member] | ProShares VIX Short-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 152,996,232 | 84,999,583
Level I - Quoted Prices [Member] | ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure | [1] | (59,803,004) | (6,364,090)
Level II - Other Significant Observable Inputs [Member] | Foreign Currency Forward Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 5,179,209 | (1,545,847)
Level II - Other Significant Observable Inputs [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | (62,923,401) | 76,644,745
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | (40,748,594) | 18,242,195
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Euro [Member] | Foreign Currency Forward Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | (222,404) | 88,736
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Gold [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 6,160,430 | 5,140,980
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Silver [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | (28,421,003) | 56,752,666
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  |  | (24,807)
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Yen [Member] | Foreign Currency Forward Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | (189,002) | 67,087
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Euro [Member] | Foreign Currency Forward Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 3,254,693 | (1,136,704)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Gold [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | (685,467) | (268,728)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Silver [Member] | Swap Agreements [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | 771,233 | (3,197,561)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Yen [Member] | Foreign Currency Forward Contracts [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments, fair value disclosure |  | $ 2,335,922 | $ (564,966)
[1] | 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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- Definition Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 35 -Paragraph 54B -URI http://asc.fasb.org/extlink&oid=117332851&loc=SL7495116-110257 + Details
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