v2.4.0.8
Significant Accounting Policies - Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares (Detail)
Mar. 31, 2014
ProShares UltraShort Silver [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 7:00 A.M.
NAV Calculation Date March 31
ProShares Ultra Silver [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 7:00 A.M.
NAV Calculation Date March 31
ProShares UltraShort Gold [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 10:00 A.M.
NAV Calculation Date March 31
ProShares Ultra Gold [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 10:00 A.M.
NAV Calculation Date March 31
ProShares UltraShort DJ-UBS Crude Oil [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 2:30 P.M.
NAV Calculation Date March 31
ProShares Ultra DJ-UBS Crude Oil [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 2:30 P.M.
NAV Calculation Date March 31
ProShares UltraShort DJ-UBS Natural Gas [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 2:30 P.M.
NAV Calculation Date March 31
ProShares Ultra DJ-UBS Natural Gas [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 2:30 P.M.
NAV Calculation Date March 31
ProShares UltraShort DJ-UBS Commodity [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 3.00 P.M.
NAV Calculation Date March 31
ProShares Ultra DJ-UBS Commodity [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 3.00 P.M.
NAV Calculation Date March 31
ProShares UltraShort Australian Dollar [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares Ultra Australian Dollar [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares Short Euro [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares UltraShort Euro [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares Ultra Euro [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares UltraShort Yen [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares Ultra Yen [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:00 P.M.
NAV Calculation Date March 31
ProShares VIX Short-Term Futures ETF [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:15 P.M.
NAV Calculation Date March 31
ProShares Ultra VIX Short-Term Futures ETF [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:15 P.M.
NAV Calculation Date March 31
ProShares Short VIX Short-Term Futures ETF [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:15 P.M.
NAV Calculation Date March 31
ProShares VIX Mid-Term Futures ETF [Member]
 
Significant Accounting Policies [Line Items]  
NAV Calculation Time 4:15 P.M.
NAV Calculation Date March 31