v2.4.0.8
Significant Accounting Policies - Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares (Parenthetical) (Detail)
6 Months Ended
Jun. 30, 2014
ProShares UltraShort Bloomberg Commodity [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 3:00 p.m.
NAV Calculation Date June 30
ProShares Ultra Bloomberg Commodity [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 3:00 p.m.
NAV Calculation Date June 30
July 31, 2014 [Member] | ProShares UltraShort Bloomberg Commodity [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 2:30 p.m.
NAV Calculation Date July 31
July 31, 2014 [Member] | ProShares Ultra Bloomberg Commodity [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 2:30 p.m.
NAV Calculation Date July 31