v3.21.1

Schedule of Investments - Futures Contracts Sold (Detail) - Futures Contracts [Member] - Contracts to Sell [Member]	Mar. 31, 2021 USD ($) Contract
ProShares Short Euro [Member] | Euro Fx Currency Futures - CME, expires June 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	15
Notional Amount at Value	$ 2,201,625
Unrealized Appreciation (Depreciation)	33,928
ProShares Short VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ 50,470,675
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires April 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	6,607
Notional Amount at Value	$ 136,989,538
Unrealized Appreciation (Depreciation)	$ 42,996,259
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	5,590
Notional Amount at Value	$ 126,757,722
Unrealized Appreciation (Depreciation)	$ 7,474,416
ProShares UltraShort Australian Dollar [Member] | Australian Dollar Fx Currency Futures - CME, expires June 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	60
Notional Amount at Value	$ 4,560,900
Unrealized Appreciation (Depreciation)	67,102
ProShares UltraShort Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (9,000,179)
ProShares UltraShort Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, expires June 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	1,020
Notional Amount at Value	$ 60,363,600
Unrealized Appreciation (Depreciation)	$ (5,808,804)
ProShares UltraShort Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, expires December 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	1,082
Notional Amount at Value	$ 61,511,700
Unrealized Appreciation (Depreciation)	$ (3,660,503)
ProShares UltraShort Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, expires June 2022 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	1,125
Notional Amount at Value	$ 61,560,000
Unrealized Appreciation (Depreciation)	$ 469,128
ProShares UltraShort Bloomberg Natural Gas [Member] | Natural Gas - NYMEX, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	5,327
Notional Amount at Value	$ 138,928,160
Unrealized Appreciation (Depreciation)	$ 16,272,857
ProShares UltraShort Gold [Member] | Gold Futures - COMEX, expires June 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	247
Notional Amount at Value	$ 42,375,320
Unrealized Appreciation (Depreciation)	$ 39,145
ProShares UltraShort Silver [Member] | Silver Futures - COMEX, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	347
Notional Amount at Value	$ 42,563,020
Unrealized Appreciation (Depreciation)	$ 3,276,894

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