v2.4.0.6

Schedule Of Investments (Short-Term U.S. Government And Agency Obligations) (Parenthetical) (Detail) (USD $) | 3 Months Ended
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Mar. 31, 2013
ProShares UltraShort DJ-UBS Commodity [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 93.00% |
Total short-term U.S. government and agency obligations, cost | $ 3,062,693 |
ProShares UltraShort DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.096% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.096% | [1]
Debt instrument, maturity date | Apr. 18, 2013 | [1]
ProShares UltraShort DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.101% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.101% | [1]
Debt instrument, maturity date | May 16, 2013 | [1]
ProShares UltraShort DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.072% due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.072% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 103.00% |
Total short-term U.S. government and agency obligations, cost | 145,470,481 |
ProShares UltraShort DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.071% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.071% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares UltraShort DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.074% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.074% | [1]
Debt instrument, maturity date | Apr. 25, 2013 | [1]
ProShares UltraShort DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.098% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.098% |
Debt instrument, maturity date | May 16, 2013 |
ProShares UltraShort DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.084% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.084% | [1]
Debt instrument, maturity date | Jun. 27, 2013 | [1]
ProShares UltraShort DJ-UBS Natural Gas [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 84.00% |
Total short-term U.S. government and agency obligations, cost | 21,192,907 |
ProShares UltraShort DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.091% due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.091% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares UltraShort DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.050% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.05% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares UltraShort DJ-UBS Natural Gas [Member] | United States Treasury Bills 0.101% due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.101% |
Debt instrument, maturity date | May 16, 2013 |
ProShares UltraShort DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.071% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.071% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares UltraShort Gold [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 103.00% |
Total short-term U.S. government and agency obligations, cost | 108,154,807 |
ProShares UltraShort Gold [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort Gold [Member] | U.S. Treasury Bills 0.060% due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.06% | [2]
Debt instrument, maturity date | Apr. 18, 2013 | [2]
ProShares UltraShort Gold [Member] | U.S. Treasury Bills 0.062% due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.062% | [2]
Debt instrument, maturity date | Apr. 25, 2013 | [2]
ProShares UltraShort Gold [Member] | U.S. Treasury Bills 0.110% due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.11% |
Debt instrument, maturity date | May 16, 2013 |
ProShares UltraShort Gold [Member] | U.S. Treasury Bills 0.087% due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.087% | [2]
Debt instrument, maturity date | Jun. 27, 2013 | [2]
ProShares UltraShort Silver [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 99.00% |
Total short-term U.S. government and agency obligations, cost | 105,343,764 |
ProShares UltraShort Silver [Member] | U.S. Treasury Bills 0.084% due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.084% | [2]
Debt instrument, maturity date | Apr. 18, 2013 | [2]
ProShares UltraShort Silver [Member] | U.S. Treasury Bills 0.063% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.063% | [2]
Debt instrument, maturity date | Apr. 25, 2013 | [2]
ProShares UltraShort Silver [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares UltraShort Silver [Member] | U.S. Treasury Bills 0.093% due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.093% | [2]
Debt instrument, maturity date | Jun. 27, 2013 | [2]
ProShares Short Euro [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 87.00% |
Total short-term U.S. government and agency obligations, cost | 3,371,937 |
ProShares Short Euro [Member] | U.S. Treasury Bills 0.101% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.101% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Short Euro [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort Australian Dollar [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 90.00% |
Total short-term U.S. government and agency obligations, cost | 3,329,947 |
ProShares UltraShort Australian Dollar [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort Australian Dollar [Member] | U.S. Treasury Bills 0.050% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.05% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares UltraShort Euro [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 98.00% |
Total short-term U.S. government and agency obligations, cost | 507,177,936 |
ProShares UltraShort Euro [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort Euro [Member] | U.S. Treasury Bills 0.054% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.054% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares UltraShort Euro [Member] | U.S. Treasury Bills 0.068% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.068% | [3]
Debt instrument, maturity date | Apr. 25, 2013 | [3]
ProShares UltraShort Euro [Member] | U.S. Treasury Bills 0.104% Due 05/16/13[Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.104% |
Debt instrument, maturity date | May 16, 2013 |
ProShares UltraShort Euro [Member] | U.S. Treasury Bills 0.095% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.095% | [3]
Debt instrument, maturity date | Jun. 27, 2013 | [3]
ProShares UltraShort Yen [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 98.00% |
Total short-term U.S. government and agency obligations, cost | 463,610,208 |
ProShares UltraShort Yen [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares UltraShort Yen [Member] | U.S. Treasury Bills 0.063% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.063% | [3]
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares UltraShort Yen [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares UltraShort Yen [Member] | U.S. Treasury Bills 0.056% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.056% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares UltraShort Yen [Member] | U.S. Treasury Bills 0.079% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.079% | [3]
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Ultra DJ-UBS Commodity [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 71.00% |
Total short-term U.S. government and agency obligations, cost | 3,350,591 |
ProShares Ultra DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.050% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.05% | [1]
Debt instrument, maturity date | Apr. 25, 2013 | [1]
ProShares Ultra DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.056% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.056% | [1]
Debt instrument, maturity date | Apr. 18, 2013 | [1]
ProShares Ultra DJ-UBS Commodity [Member] | U.S. Treasury Bills 0.076% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.076% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Ultra DJ-UBS Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 93.00% |
Total short-term U.S. government and agency obligations, cost | 303,993,548 |
ProShares Ultra DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares Ultra DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.079% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.079% | [1]
Debt instrument, maturity date | Jun. 27, 2013 | [1]
ProShares Ultra DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.103% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares Ultra DJ-UBS Crude Oil [Member] | U.S. Treasury Bills 0.055% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% | [1]
Debt instrument, maturity date | Apr. 25, 2013 | [1]
ProShares Ultra DJ-UBS Natural Gas [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 105.00% |
Total short-term U.S. government and agency obligations, cost | 53,700,121 |
ProShares Ultra DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.103% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares Ultra DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.059% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.059% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares Ultra DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.103% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra DJ-UBS Natural Gas [Member] | U.S. Treasury Bills 0.082% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.082% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Ultra Gold [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 97.00% |
Total short-term U.S. government and agency obligations, cost | 307,376,479 |
ProShares Ultra Gold [Member] | U.S. Treasury Bills 0.050% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.05% | [2]
Debt instrument, maturity date | Apr. 25, 2013 | [2]
ProShares Ultra Gold [Member] | U.S. Treasury Bills 0.056% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.056% | [2]
Debt instrument, maturity date | Apr. 18, 2013 | [2]
ProShares Ultra Gold [Member] | U.S. Treasury Bills 0.076% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.076% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Ultra Gold [Member] | U.S. Treasury Bills 0.094% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.094% | [2]
Debt instrument, maturity date | May 16, 2013 | [2]
ProShares Ultra Silver [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 101.00% |
Total short-term U.S. government and agency obligations, cost | 754,938,086 |
ProShares Ultra Silver [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% | [2]
Debt instrument, maturity date | May 16, 2013 | [2]
ProShares Ultra Silver [Member] | U.S. Treasury Bills 0.055% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% | [2]
Debt instrument, maturity date | Apr. 25, 2013 | [2]
ProShares Ultra Silver [Member] | U.S. Treasury Bills 0.069% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.069% | [2]
Debt instrument, maturity date | Apr. 11, 2013 | [2]
ProShares Ultra Silver [Member] | U.S. Treasury Bills 0.078% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.078% | [2]
Debt instrument, maturity date | Jun. 27, 2013 | [2]
ProShares Ultra Australian Dollar [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 87.00% |
Total short-term U.S. government and agency obligations, cost | 3,676,855 |
ProShares Ultra Australian Dollar [Member] | U.S. Treasury Bills 0.055% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.055% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares Ultra Australian Dollar [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra Australian Dollar [Member] | U.S. Treasury Bills 0.051% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.051% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares Ultra Australian Dollar [Member] | U.S. Treasury Bills 0.065% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.065% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares Ultra Australian Dollar [Member] | U.S. Treasury Bills 0.070% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.07% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Ultra Euro [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 98.00% |
Total short-term U.S. government and agency obligations, cost | 4,478,870 |
ProShares Ultra Euro [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra Euro [Member] | U.S. Treasury Bills 0.056% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.056% | [3]
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares Ultra Euro [Member] | U.S. Treasury Bills 0.058% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.058% | [3]
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares Ultra Yen [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 99.00% |
Total short-term U.S. government and agency obligations, cost | 3,534,876 |
ProShares Ultra Yen [Member] | U.S. Treasury Bills 0.105% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.105% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra Yen [Member] | U.S. Treasury Bills 0.066% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.066% | [3]
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares VIX Short-Term Futures ETF [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 70.00% |
Total short-term U.S. government and agency obligations, cost | 152,933,255 |
ProShares VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.050% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.05% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.103% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.103% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | May 16, 2013 |
ProShares VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.070% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.07% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.058% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.058% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares VIX Mid-Term Futures ETF [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 73.00% |
Total short-term U.S. government and agency obligations, cost | 49,700,662 |
ProShares VIX Mid-Term Futures ETF [Member] | U.S. Treasury Bills 0.103% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | May 16, 2013 |
ProShares VIX Mid-Term Futures ETF [Member] | U.S. Treasury Bills 0.078% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.078% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares VIX Mid-Term Futures ETF [Member] | U.S. Treasury Bills 0.068% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.068% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares VIX Mid-Term Futures ETF [Member] | U.S. Treasury Bills 0.051% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.051% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 34.00% |
Total short-term U.S. government and agency obligations, cost | 118,784,627 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.101% Due 05/16/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.101% |
Debt instrument, maturity date | May 16, 2013 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.103% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.056% Due 04/11/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.056% |
Debt instrument, maturity date | Apr. 11, 2013 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.052% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.052% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares Ultra VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.069% Due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.069% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Schedule of Investments [Line Items] |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | 66.00% |
Total short-term U.S. government and agency obligations, cost | $ 45,829,953 |
ProShares Short VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.072% due 06/27/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.072% |
Debt instrument, maturity date | Jun. 27, 2013 |
ProShares Short VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.103% Due 04/18/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.103% |
Debt instrument, maturity date | Apr. 18, 2013 |
ProShares Short VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.108% Due 04/25/13 [Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.108% |
Debt instrument, maturity date | Apr. 25, 2013 |
ProShares Short VIX Short-Term Futures ETF [Member] | U.S. Treasury Bills 0.096% Due 05/16/13[Member] |  |
Schedule of Investments [Line Items] |  |
Interest rate | 0.096% |
Debt instrument, maturity date | May 16, 2013 |
[1] | All or partial amount pledged as collateral for swap agreements.
[2] | All or partial amount pledged as collateral for forward agreements.
[3] | All or partial amount pledged as collateral for foreign currency forward contracts.

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- Definition Short-term U.S. government and agency obligations, cost + References No definition available. + Details
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- Definition Short Term U S Government And Agency Obligations Of Shareholders Equity + References No definition available. + Details
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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Details
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