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	0us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
ProShares Ultra Bloomberg Commodity [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Split Ratio		0.25us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember	0.25us-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		0.25us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember	0.25us-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		0.25us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember	0.25us-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		0.20us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember	0.20us-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		0.20us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember	0.20us-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

Nine character alphanumeric identifier of an entity or issuer and the type of security.

+ References

No definition available.

+ Details

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X

- 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

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