v3.8.0.1

Organization - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2017 USD ($) Trust shares
Organization [Line Items]
Number of series of Trust | Trust	20
Number of shares of each Leveraged Fund | shares	14
Aggregate purchase price of each Leveraged Fund	$ 350
Period for expected multiple returns	1 day
ProShares UltraShort Bloomberg Crude Oil [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	$ 350
ProShares UltraShort Gold [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares UltraShort Silver [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares UltraShort Euro [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares UltraShort Yen [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares Ultra Bloomberg Crude Oil [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares Ultra Gold [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares Ultra Silver [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares Ultra Euro [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350
ProShares Ultra Yen [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	$ 350

X

- Definition

Aggregate purchase of each fund.

+ References

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+ Details

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X

- Definition

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+ References

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X

- Definition

Number of shares of each fund.

+ References

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+ Details

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X

- Definition

Organization.

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- Definition

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- Details

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- Details

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- Details

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- Details

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- Details

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