v3.10.0.1

Organization - Schedule of Share Splits and Reverse Share Splits (Detail)	6 Months Ended
	Jun. 30, 2018
ProShares UltraShort Bloomberg Crude Oil [Member] | January 11, 2017 Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jan. 11, 2017
Date Trading Resumed at Post- Split Price	Jan. 12, 2017
Type of Split	2-for-1 Share split
ProShares Ultra Bloomberg Crude Oil [Member] | January 11, 2017 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jan. 11, 2017
Date Trading Resumed at Post- Split Price	Jan. 12, 2017
Type of Split	1-for-2 reverse Share split
ProShares Ultra VIX Short-Term Futures ETF [Member] | January 11, 2017 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jan. 11, 2017
Date Trading Resumed at Post- Split Price	Jan. 12, 2017
Type of Split	1-for-5 reverse Share split
ProShares Ultra VIX Short-Term Futures ETF [Member] | July 14, 2017 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jul. 14, 2017
Date Trading Resumed at Post- Split Price	Jul. 17, 2017
Type of Split	1-for-4 reverse Share split
ProShares Short VIX Short-Term Futures ETF [Member] | July 12, 2017 Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jul. 12, 2017
Date Trading Resumed at Post- Split Price	Jul. 17, 2017
Type of Split	2-for-1 Share split
ProShares VIX Short-Term Futures ETF [Member] | July 14, 2017 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jul. 14, 2017
Date Trading Resumed at Post- Split Price	Jul. 17, 2017
Type of Split	1-for-4 reverse Share split
ProShares Ultra Bloomberg Natural Gas [Member] | March 19, 2018 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Mar. 19, 2018
Date Trading Resumed at Post- Split Price	Mar. 20, 2018
Type of Split	1-for-5 reverse Share split
ProShares UltraPro 3X Short Crude Oil ETF [Member] | March 19, 2018 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Mar. 19, 2018
Date Trading Resumed at Post- Split Price	Mar. 20, 2018
Type of Split	1-for-4 reverse Share split

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- Definition

Description of the stock split arrangement. Also provide the retroactive effect given by a stock split that occurs after the balance date but before the release of financial statements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.C)
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+ References

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-Publisher FASB
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