v3.8.0.1
Schedule of Investments - Forward Agreements (Detail)
 9 Months Ended
Sep. 30, 2017
USD ($)
 [1]
ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) $ 2,961,605
ProShares UltraShort Gold [Member] | Forward agreements with Citibank N.A. based on 0.995 Fine Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.30%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (16,100)
Notional Amount at Value (20,663,223) [3]
Unrealized Appreciation (Depreciation) $ 1,045,390
ProShares UltraShort Gold [Member] | Forward agreements with Goldman Sachs International based on 0.995 Fine Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.06%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (16,898)
Notional Amount at Value (21,687,062) [3]
Unrealized Appreciation (Depreciation) $ 835,086
ProShares UltraShort Gold [Member] | Forward agreements with Societe Generale based on 0.995 Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.01%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (4,800)
Notional Amount at Value (6,160,368) [3]
Unrealized Appreciation (Depreciation) $ 267,146
ProShares UltraShort Gold [Member] | Forward agreements with UBS AG based on 0.995 Fine Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.05%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (17,250)
Notional Amount at Value (22,138,823) [3]
Unrealized Appreciation (Depreciation) 813,983
ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) $ 2,152,433
ProShares UltraShort Silver [Member] | Forward agreements with Citibank N.A. based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.40%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (953,000)
Notional Amount at Value (16,071,964) [3]
Unrealized Appreciation (Depreciation) $ 775,445
ProShares UltraShort Silver [Member] | Forward agreements with Goldman Sachs International based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.18%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (786,500)
Notional Amount at Value (13,263,851) [3]
Unrealized Appreciation (Depreciation) $ 671,956
ProShares UltraShort Silver [Member] | Forward agreements with Societe Generale based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.14%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (156,000)
Notional Amount at Value (2,630,862) [3]
Unrealized Appreciation (Depreciation) $ 143,987
ProShares UltraShort Silver [Member] | Forward agreements with UBS AG based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) (1.13%) [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ (814,000)
Notional Amount at Value (13,727,622) [3]
Unrealized Appreciation (Depreciation) 561,045
ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) $ (8,453,427)
ProShares Ultra Gold [Member] | Forward agreements with Citibank N.A. based on 0.995 Fine Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 1.80% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 44,400
Notional Amount at Value 56,984,292 [3]
Unrealized Appreciation (Depreciation) $ (2,994,458)
ProShares Ultra Gold [Member] | Forward agreements with Goldman Sachs International based on 0.995 Fine Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 1.91% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 38,120
Notional Amount at Value 48,923,589 [3]
Unrealized Appreciation (Depreciation) $ (2,118,074)
ProShares Ultra Gold [Member] | Forward agreements with Societe Generale based on 0.995 Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 1.91% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 18,000
Notional Amount at Value 23,101,380 [3]
Unrealized Appreciation (Depreciation) $ (1,015,643)
ProShares Ultra Gold [Member] | Forward agreements with UBS AG based on 0.995 Fine Troy Ounce Gold [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 1.85% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 38,900
Notional Amount at Value 49,924,649 [3]
Unrealized Appreciation (Depreciation) (2,325,252)
ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Unrealized Appreciation (Depreciation) $ (28,243,802)
ProShares Ultra Silver [Member] | Forward agreements with Citibank N.A. based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 1.90% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 9,604,000
Notional Amount at Value 161,967,618 [3]
Unrealized Appreciation (Depreciation) $ (9,405,158)
ProShares Ultra Silver [Member] | Forward agreements with Goldman Sachs International based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 2.03% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 7,795,800
Notional Amount at Value 131,471,490 [3]
Unrealized Appreciation (Depreciation) $ (7,478,422)
ProShares Ultra Silver [Member] | Forward agreements with Societe Generale based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 2.04% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 3,784,000
Notional Amount at Value 63,815,268 [3]
Unrealized Appreciation (Depreciation) $ (3,531,263)
ProShares Ultra Silver [Member] | Forward agreements with UBS AG based on 0.999 Fine Troy Ounce Silver [Member]  
Schedule of Investments [Line Items]  
Rate Paid (Received) 2.03% [2]
Settlement Date Oct. 05, 2017
Commitment to (Deliver)/Receive $ 7,836,000
Notional Amount at Value 132,149,438 [3]
Unrealized Appreciation (Depreciation) $ (7,828,959)
[1] The positions and counterparties herein are as of September 30, 2017. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.
[2] Reflects the floating financing rate, as of September 30, 2017, on the notional amount of the forward agreement paid to the counterparty or received from the counterparty, excluding any commissions.
[3] For forward agreements, a positive amount represents "long" exposure to the underlying commodity. A negative amount represents "short" exposure to the underlying commodity.