v2.4.1.9

Subsequent Events - Schedule of Each Funds Going Under Reverse Stock Splits (Detail) | 3 Months Ended | 0 Months Ended
--- | --- | ---
Mar. 31, 2015 | May 20, 2015 | May 01, 2015
Subsequent Event [Line Items] |  |  |
Split Ratio | 0 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 |  |
ProShares Ultra Bloomberg Commodity [Member] | Subsequent Event [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Split Ratio |  | 0.25 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 0.25 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
ProShares Ultra Bloomberg Commodity [Member] | Subsequent Event [Member] | Old CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W106 |
ProShares Ultra Bloomberg Commodity [Member] | Subsequent Event [Member] | New CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W288 |
ProShares Ultra Bloomberg Natural Gas [Member] | Subsequent Event [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Split Ratio |  | 0.25 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 0.25 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
ProShares Ultra Bloomberg Natural Gas [Member] | Subsequent Event [Member] | Old CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W122 |
ProShares Ultra Bloomberg Natural Gas [Member] | Subsequent Event [Member] | New CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W296 |
ProShares Ultra Yen [Member] | Subsequent Event [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Split Ratio |  | 0.25 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 0.25 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
ProShares Ultra Yen [Member] | Subsequent Event [Member] | Old CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W866 |
ProShares Ultra Yen [Member] | Subsequent Event [Member] | New CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W270 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | Subsequent Event [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Split Ratio |  | 0.20 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 0.20 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
ProShares Ultra VIX Short-Term Futures ETF [Member] | Subsequent Event [Member] | Old CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W346 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | Subsequent Event [Member] | New CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W312 |
ProShares Ultra Bloomberg Crude Oil [Member] | Subsequent Event [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Split Ratio |  | 0.20 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 0.20 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
ProShares Ultra Bloomberg Crude Oil [Member] | Subsequent Event [Member] | Old CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W650 |
ProShares Ultra Bloomberg Crude Oil [Member] | Subsequent Event [Member] | New CUSIP [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Committee for Uniform Securities Identification Procedures (CUSIP) |  | 74347W320 |

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- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. + 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 + Details
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