v3.21.1

Schedule of Investments - Futures Contracts Purchased (Detail) - Futures Contracts [Member] - Contracts to Purchase [Member]	Mar. 31, 2021 USD ($) Contract bbl
ProShares Ultra Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Total Unrealized (Depreciation)	$ 238,548,911
ProShares Ultra Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, expires June 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	8,933
Notional Amount at Value	$ 528,654,940
Total Unrealized (Depreciation)	$ 141,467,113
ProShares Ultra Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, expires December 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	9,478
Notional Amount at Value	$ 538,824,300
Total Unrealized (Depreciation)	$ 97,420,187
ProShares Ultra Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, expires June 2022 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	9,857
Notional Amount at Value	$ 539,375,040
Total Unrealized (Depreciation)	$ (338,389)
ProShares Ultra Bloomberg Natural Gas [Member] | Natural Gas - NYMEX, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	5,698
Notional Amount at Value	$ 148,603,840
Total Unrealized (Depreciation)	$ (11,300,062)
ProShares Ultra Gold [Member] | Gold Futures - COMEX, expires June 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | bbl	722
Notional Amount at Value	$ 123,866,320
Total Unrealized (Depreciation)	$ 393,125
ProShares Ultra Silver [Member] | Silver Futures - COMEX, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | bbl	1,667
Notional Amount at Value	$ 204,474,220
Total Unrealized (Depreciation)	(15,401,821)
ProShares Ultra VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Total Unrealized (Depreciation)	$ (332,928,249)
ProShares Ultra VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires April 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	45,234
Notional Amount at Value	$ 937,881,756
Total Unrealized (Depreciation)	$ (271,592,637)
ProShares Ultra VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	38,279
Notional Amount at Value	$ 868,006,948
Total Unrealized (Depreciation)	(61,335,612)
ProShares VIX Mid-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Total Unrealized (Depreciation)	$ (9,410,288)
ProShares VIX Mid-Term Futures ETF [Member] | VIX Futures - CBOE, expires July 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	550
Notional Amount at Value	$ 13,365,000
Total Unrealized (Depreciation)	$ (938,335)
ProShares VIX Mid-Term Futures ETF [Member] | VIX Futures - CBOE, expires August 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	1,016
Notional Amount at Value	$ 24,842,318
Total Unrealized (Depreciation)	$ (3,842,774)
ProShares VIX Mid-Term Futures ETF [Member] | VIX Futures - CBOE, expires September 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	1,016
Notional Amount at Value	$ 25,249,530
Total Unrealized (Depreciation)	$ (4,020,035)
ProShares VIX Mid-Term Futures ETF [Member] | VIX Futures - CBOE, expires October 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	466
Notional Amount at Value	$ 11,653,868
Total Unrealized (Depreciation)	(609,144)
ProShares VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Total Unrealized (Depreciation)	$ (59,803,004)
ProShares VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires April 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	8,754
Notional Amount at Value	$ 181,505,436
Total Unrealized (Depreciation)	$ (48,339,299)
ProShares VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires May 2021 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	7,407
Notional Amount at Value	$ 167,959,651
Total Unrealized (Depreciation)	$ (11,463,705)

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