v2.4.1.9

Organization - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015 Trust
Organization [Line Items]
Number of series of Trust	22ck0001415311_NumberOfSeries
Number of shares of each Leveraged Fund	14ck0001415311_NumberOfSharesOfEachFund
Aggregate purchase price of each Leveraged Fund	$ 350ck0001415311_AggregatePurchaseOfEachFund
Period for expected multiple returns	1 day
Funds Split	There were no Share splits during the three months ended March 31, 2015.
Funds Reverse Split	There were no reverse Share splits during the three months ended March 31, 2015.
Split Ratio	0us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
ProShares UltraShort Bloomberg Commodity [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember
ProShares UltraShort Bloomberg Crude Oil [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
ProShares UltraShort Gold [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
ProShares UltraShort Silver [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
ProShares UltraShort Euro [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
ProShares UltraShort Yen [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
ProShares Ultra Bloomberg Commodity [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember
ProShares Ultra Bloomberg Crude Oil [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
ProShares Ultra Gold [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
ProShares Ultra Silver [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
ProShares Ultra Euro [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember
ProShares Ultra Yen [Member]
Organization [Line Items]
Aggregate purchase price of each Leveraged Fund	$ 350ck0001415311_AggregatePurchaseOfEachFund / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember

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-Publisher FASB

-Name Accounting Standards Codification

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