v3.8.0.1

Organization - Schedule of Share Splits and Reverse Share Splits (Detail)	9 Months Ended
	Sep. 30, 2017
ProShares UltraShort Bloomberg Natural Gas [Member] | July 20, 2016 Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jul. 20, 2016
Date Trading Resumed at Post- Split Price	Jul. 25, 2016
Type of Split	3-for-1 Share split
ProShares VIX Short-Term Futures ETF [Member] | July 25, 2016 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jul. 25, 2016
Date Trading Resumed at Post- Split Price	Jul. 25, 2016
Type of Split	1-for-5 reverse Share split
ProShares VIX Short-Term Futures ETF [Member] | July Fourteen Two Thousand And Seventeen 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 VIX Short-Term Futures ETF [Member] | July 25, 2016 Reverse Share Split [Member]
Organization [Line Items]
Execution Date (Prior to Opening of Trading)	Jul. 25, 2016
Date Trading Resumed at Post- Split Price	Jul. 25, 2016
Type of Split	1-for-5 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 Fourteen Two Thousand And Seventeen 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 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 Short VIX Short-Term Futures ETF [Member] | July Twelve Two Thousand And Seventeen 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

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- Definition

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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