v2.4.0.8

Organization - Schedule of Share Splits and Reverse Share Splits (Detail) | 0 Months Ended
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Jan. 21, 2014 | Jun. 10, 2013
ProShares UltraShort DJ-UBS Natural Gas [Member] |  |
Organization [Line Items] |  |
Execution Date (Prior to Opening of Trading) |  | June 10, 2013
Date Trading Resumed at Post- Split Price |  | June 10, 2013
Funds Reverse Split |  | 1-for-4 reverse Share split
ProShares Ultra Silver [Member] |  |
Organization [Line Items] |  |
Execution Date (Prior to Opening of Trading) | January 21, 2014 |
Date Trading Resumed at Post- Split Price | January 24, 2014 |
Funds Reverse Split | 1-for-4 reverse Share split |
ProShares VIX Short-Term Futures ETF [Member] |  |
Organization [Line Items] |  |
Execution Date (Prior to Opening of Trading) |  | June 10, 2013
Date Trading Resumed at Post- Split Price |  | June 10, 2013
Funds Reverse Split |  | 1-for-5 reverse Share split
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Organization [Line Items] |  |
Execution Date (Prior to Opening of Trading) | January 21, 2014 | June 10, 2013
Date Trading Resumed at Post- Split Price | January 24, 2014 | June 10, 2013
Funds Reverse Split | 1-for-4 reverse Share split | 1-for-10 reverse Share split
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Organization [Line Items] |  |
Execution Date (Prior to Opening of Trading) | January 21, 2014 |
Date Trading Resumed at Post- Split Price | January 24, 2014 |
Funds Split | 2-for-1 Share split |

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- Definition Post split price, trading resumed date. + References No definition available. + Details
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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 -Glossary Stock Split -URI http://asc.fasb.org/extlink&oid=6525746 Reference 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section C + Details
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- Definition 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section C + Details
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