v3.21.1

Investments - Fair Value of Derivative Instruments (Detail) - Not Designated as Hedging Instrument [Member] - USD ($)		Mar. 31, 2021	Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	$ 322,651,846	$ 280,082,746
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	509,137,004	76,613,676
VIX Futures Contracts [Member] | Payable on open futures contracts, unrealized depreciation on swap agreements [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	332,928,249	48,549,473
VIX Futures Contracts [Member] | Payable on open futures contracts, unrealized depreciation on swap agreements [Member] | ProShares VIX Mid-Term Futures ETF [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	9,410,288	1,281,531
VIX Futures Contracts [Member] | Payable on open futures contracts, unrealized depreciation on swap agreements [Member] | ProShares VIX Short-Term Futures ETF [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	59,803,004	6,364,090
VIX Futures Contracts [Member] | Receivables on open futures contracts, unrealized appreciation on swap agreements [Member] | ProShares Short VIX Short-Term Futures ETF [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	50,470,675	8,348,783
VIX Futures Contracts [Member] | Receivables on open futures contracts, unrealized appreciation on swap agreements [Member] | ProShares VIX Mid-Term Futures ETF [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]		147,915
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	9,469,307	14,636,813
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares UltraShort Gold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	685,467	465,658
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares UltraShort Silver [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]		3,417,637
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares Ultra Bloomberg Crude Oil [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	41,086,983
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares Ultra Bloomberg Natural Gas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	11,300,062
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares Ultra Silver [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]	43,822,824
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	469,128
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	16,272,857	379,310
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Gold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	39,145
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Silver [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	4,048,127
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Bloomberg Crude Oil [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	238,887,300	162,806,234
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Bloomberg Natural Gas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]		6,500,721
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Gold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	6,553,555	7,787,854
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Silver [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]		93,942,878
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares Short Euro [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]		44,626
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares Ultra Euro [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation		226,734	367
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares UltraShort Australian Dollar [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation	[1]		138,950
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares Ultra Yen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation		192,043	148
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares UltraShort Euro [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation		181,875	1,142,409
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares UltraShort Yen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability not accounted as hedging instrument, Unrealized Depreciation		30,168	571,974
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares Short Euro [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	33,928
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares Ultra Euro [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation		4,330	89,103
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares UltraShort Australian Dollar [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation	[1]	67,102
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares Ultra Yen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation		3,041	67,235
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares UltraShort Euro [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation		3,436,568	5,705
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares UltraShort Yen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative asset not designated as hedging instrument, Unrealized Appreciation		$ 2,366,090	$ 7,008
[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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+ References

No definition available.

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+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 22
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