v2.4.0.6

Organization (Schedule of Share Splits and Reverse Share Splits) (Detail) | 1 Months Ended
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Feb. 25, 2011 ProShares UltraShort DJ-UBS Commodity [Member] | Feb. 25, 2011 ProShares UltraShort DJ-UBS Crude Oil [Member] | May 11, 2012 ProShares UltraShort DJ-UBS Natural Gas [Member] | Oct. 05, 2012 ProShares UltraShort Gold [Member] | May 11, 2012 ProShares UltraShort Silver [Member] | Feb. 25, 2011 ProShares UltraShort Silver [Member] | Oct. 13, 2011 ProShares UltraShort Yen [Member] | Feb. 25, 2011 ProShares Ultra DJ-UBS Crude Oil [Member] | May 11, 2012 ProShares Ultra DJ-UBS Natural Gas [Member] | Oct. 13, 2011 ProShares Ultra Silver [Member] | Sep. 07, 2012 ProShares Ultra VIX Short-Term Futures ETF [Member] | Mar. 08, 2012 ProShares Ultra VIX Short-Term Futures ETF [Member] | Oct. 05, 2012 ProShares Short VIX Short-Term Futures ETF [Member]
Organization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Funds Reverse Split | 1-for-5 reverse Share split | 1-for-5 reverse Share split |  | 1-for-4 reverse Share split | 1-for-5 reverse Share split | 1-for-4 reverse Share split | 1-for-3 reverse Share split | 1-for-4 reverse Share split | 1-for-5 reverse Share split |  | 1-for-10 reverse Share split | 1-for-6 reverse Share split |
Funds Split |  |  | 3-for-1 Share split |  |  |  |  |  |  | 2-for-1 Share split |  |  | 2-for-1 Share split
Execution date prior to opening of trading | February 25, 2011 | February 25, 2011 | May 11, 2012 | October 5, 2012 | May 11, 2012 | February 25, 2011 | October 13, 2011 | February 25, 2011 | May 11, 2012 | October 13, 2011 | September 7, 2012 | March 8, 2012 | October 5, 2012
Trading date resumed at post- split price | February 25, 2011 | February 25, 2011 | May 11, 2012 | October 5, 2012 | May 11, 2012 | February 25, 2011 | October 13, 2011 | February 25, 2011 | May 11, 2012 | October 13, 2011 | September 7, 2012 | March 8, 2012 | October 5, 2012

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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 AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Section B -Paragraph 2, 15, 16 -Chapter 7 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: 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 3: 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=6959260&loc=d3e187143-122770 Reference 4: 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 Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 54 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. 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=6959260&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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