v2.4.0.6

STATEMENTS OF FINANCIAL CONDITION (Parenthetical) (USD $) | Mar. 31, 2013 | Dec. 31, 2012
--- | --- | ---
ProShares UltraShort DJ-UBS Commodity [Member] |  |
Short-term U.S. government and agency obligations, cost | $ 3,062,693 | $ 2,803,598
ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Short-term U.S. government and agency obligations, cost | 145,470,481 | 87,042,320
ProShares UltraShort DJ-UBS Natural Gas [Member] |  |
Short-term U.S. government and agency obligations, cost | 21,192,907 | 10,042,198
ProShares UltraShort Gold [Member] |  |
Short-term U.S. government and agency obligations, cost | 108,154,807 | 88,573,928
ProShares UltraShort Silver [Member] |  |
Short-term U.S. government and agency obligations, cost | 105,343,764 | 86,199,868
ProShares Short Euro [Member] |  |
Short-term U.S. government and agency obligations, cost | 3,371,937 | 3,409,716
ProShares UltraShort Australian Dollar [Member] |  |
Short-term U.S. government and agency obligations, cost | 3,329,947 | 3,302,725
ProShares UltraShort Euro [Member] |  |
Short-term U.S. government and agency obligations, cost | 507,177,936 | 553,417,216
ProShares UltraShort Yen [Member] |  |
Short-term U.S. government and agency obligations, cost | 463,610,208 | 362,731,936
ProShares Ultra DJ-UBS Commodity [Member] |  |
Short-term U.S. government and agency obligations, cost | 3,350,591 | 6,240,818
ProShares Ultra DJ-UBS Crude Oil [Member] |  |
Short-term U.S. government and agency obligations, cost | 303,993,548 | 437,644,628
ProShares Ultra DJ-UBS Natural Gas [Member] |  |
Short-term U.S. government and agency obligations, cost | 53,700,121 | 64,312,441
ProShares Ultra Gold [Member] |  |
Short-term U.S. government and agency obligations, cost | 307,376,479 | 350,608,755
ProShares Ultra Silver [Member] |  |
Short-term U.S. government and agency obligations, cost | 754,938,086 | 891,006,493
ProShares Ultra Australian Dollar [Member] |  |
Short-term U.S. government and agency obligations, cost | 3,676,855 | 3,570,687
ProShares Ultra Euro [Member] |  |
Short-term U.S. government and agency obligations, cost | 4,478,870 | 4,546,872
ProShares Ultra Yen [Member] |  |
Short-term U.S. government and agency obligations, cost | 3,534,876 | 4,587,701
ProShares VIX Short-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 152,933,255 | 144,057,296
ProShares VIX Mid-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 49,700,662 | 79,927,870
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 118,784,627 | 97,445,279
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Short-term U.S. government and agency obligations, cost | 45,829,953 | 53,683,800
ProShares Trust II [Member] |  |
Short-term U.S. government and agency obligations, cost | $ 3,163,012,603 | $ 3,335,156,145

X
- Definition Short-term U.S. government and agency obligations, cost + References No definition available. + Details
Name: | ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
Namespace Prefix: | ck0001415311_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant