v2.4.0.6
Schedule of Investments (Swap Agreements) (Detail) (USD $)
Mar. 31, 2013
ProShares UltraShort DJ-UBS Commodity [Member]
 
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) $ (92,919) [1]
ProShares UltraShort DJ-UBS Commodity [Member] | Swap agreement with Goldman Sachs International based on Dow Jones-UBS Commodity Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value (4,670,170) [1],[2]
Unrealized Appreciation (Depreciation) (64,434) [1]
ProShares UltraShort DJ-UBS Commodity [Member] | Swap agreement with UBS AG based on Dow Jones-UBS Commodity Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value (1,918,450) [1],[2]
Unrealized Appreciation (Depreciation) (28,485) [1]
ProShares UltraShort DJ-UBS Crude Oil [Member]
 
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) (11,368,414) [1]
ProShares UltraShort DJ-UBS Crude Oil [Member] | Swap Agreement with Goldman Sachs International Based on Dow Jones UBS WTI Crude Oil Sub Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value (73,765,493) [1],[2]
Unrealized Appreciation (Depreciation) (6,252,210) [1]
ProShares UltraShort DJ-UBS Crude Oil [Member] | Swap agreement with Societe Generale S.A. based on Dow Jones-UBS Crude Oil Sub-Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value (17,320,352) [1],[2]
Unrealized Appreciation (Depreciation) (1,130,052) [1]
ProShares UltraShort DJ-UBS Crude Oil [Member] | Swap agreement with UBS AG based on Dow Jones-UBS Crude Oil Sub-Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value (42,736,934) [1],[2]
Unrealized Appreciation (Depreciation) (3,986,152) [1]
ProShares Ultra DJ-UBS Commodity [Member]
 
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) 115,047 [1]
ProShares Ultra DJ-UBS Commodity [Member] | Swap agreement with Goldman Sachs International based on Dow Jones-UBS Commodity Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value 5,220,934 [1],[2]
Unrealized Appreciation (Depreciation) 63,644 [1]
ProShares Ultra DJ-UBS Commodity [Member] | Swap agreement with UBS AG based on Dow Jones-UBS Commodity Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value 4,253,708 [1],[2]
Unrealized Appreciation (Depreciation) 51,403 [1]
ProShares Ultra DJ-UBS Crude Oil [Member]
 
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) 25,193,571 [1]
ProShares Ultra DJ-UBS Crude Oil [Member] | Swap Agreement with Goldman Sachs International Based on Dow Jones UBS WTI Crude Oil Sub Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value 136,569,546 [1],[2]
Unrealized Appreciation (Depreciation) 8,318,017 [1]
ProShares Ultra DJ-UBS Crude Oil [Member] | Swap agreement with Societe Generale S.A. based on Dow Jones-UBS Crude Oil Sub-Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value 70,834,560 [1],[2]
Unrealized Appreciation (Depreciation) 4,601,585 [1]
ProShares Ultra DJ-UBS Crude Oil [Member] | Swap agreement with UBS AG based on Dow Jones-UBS Crude Oil Sub-Index [Member]
 
Schedule of Investments [Line Items]  
Termination Date Apr. 08, 2013 [1]
Notional Amount at Value 171,781,631 [1],[2]
Unrealized Appreciation (Depreciation) $ 12,273,969 [1]
[1] The positions and counterparties herein are as of March 31, 2013. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.
[2] For swap agreements, a positive amount represents "long" exposure to the benchmark index. A negative amount represents "short" exposure to the benchmark index.