v2.4.0.8

Financial Highlights - Per Share Operating Performance (Detail) (USD $) | 3 Months Ended
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Mar. 31, 2014 | Mar. 31, 2013
ProShares UltraShort DJ-UBS Commodity [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 63.2936 | $ 54.1021
Net investment income (loss) | $ (0.1332) | $ (0.1143)
Net realized and unrealized gain (loss) | $ (8.4288) | $ 1.1149
Change in net asset value from operations | $ (8.5620) | $ 1.0006
Net asset value, ending balance | $ 54.7316 | $ 55.1027
Market value per share, beginning balance | $ 58.41 | $ 51.64
Market value per share, ending balance | $ 55.25 | $ 51.14
Total Return, at net asset value | (13.50%) | 1.80%
Total Return, at market value | (5.40%) | (1.00%)
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.91%) | (0.86%)
ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 31.7301 | $ 40.3079
Net investment income (loss) | $ (0.0690) | $ (0.0850)
Net realized and unrealized gain (loss) | $ (3.1766) | $ (3.7437)
Change in net asset value from operations | $ (3.2456) | $ (3.8287)
Net asset value, ending balance | $ 28.4845 | $ 36.4792
Market value per share, beginning balance | $ 31.58 | $ 40.44
Market value per share, ending balance | $ 28.54 | $ 36.62
Total Return, at net asset value | (10.20%) | (9.50%)
Total Return, at market value | (9.60%) | (9.40%)
Ratios to Average Net Assets |  |
Expense ratio | (0.97%) | (0.97%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.91%) | (0.90%)
ProShares UltraShort DJ-UBS Natural Gas [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 69.9635 | $ 102.1402
Net investment income (loss) | $ (0.1225) | $ (0.2565)
Net realized and unrealized gain (loss) | $ (25.9326) | $ (30.0196)
Change in net asset value from operations | $ (26.0551) | $ (30.2761)
Net asset value, ending balance | $ 43.9084 | $ 71.8641
Market value per share, beginning balance | $ 69.36 | $ 101.64
Market value per share, ending balance | $ 43.71 | $ 72.24
Total Return, at net asset value | (37.20%) | (29.60%)
Total Return, at market value | (37.00%) | (28.90%)
Ratios to Average Net Assets |  |
Expense ratio | (1.17%) | (1.21%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (1.12%) | (1.15%)
ProShares UltraShort Gold [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 103.5180 | $ 63.8688
Net investment income (loss) | $ (0.1979) | $ (0.1428)
Net realized and unrealized gain (loss) | $ (15.0246) | $ 4.1421
Change in net asset value from operations | $ (15.2225) | $ 3.9993
Net asset value, ending balance | $ 88.2955 | $ 67.8681
Market value per share, beginning balance | $ 103.53 | $ 62.60
Market value per share, ending balance | $ 89.45 | $ 68.01
Total Return, at net asset value | (14.70%) | 6.30%
Total Return, at market value | (13.60%) | 8.60%
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.89%) | (0.88%)
ProShares UltraShort Silver [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 89.7820 | $ 51.3951
Net investment income (loss) | $ (0.1773) | $ (0.1068)
Net realized and unrealized gain (loss) | $ (6.8730) | $ 2.7733
Change in net asset value from operations | $ (7.0503) | $ 2.6665
Net asset value, ending balance | $ 82.7317 | $ 54.0616
Market value per share, beginning balance | $ 90.19 | $ 50.07
Market value per share, ending balance | $ 84.24 | $ 55.02
Total Return, at net asset value | (7.90%) | 5.20%
Total Return, at market value | (6.60%) | 9.90%
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.89%) | (0.87%)
ProShares Short Euro [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 35.5867 | $ 37.6285
Net investment income (loss) | $ (0.0799) | $ (0.0840)
Net realized and unrealized gain (loss) | $ 0.0037 | $ 1.0874
Change in net asset value from operations | $ (0.0762) | $ 1.0034
Net asset value, ending balance | $ 35.5105 | $ 38.6319
Market value per share, beginning balance | $ 35.66 | $ 37.64
Market value per share, ending balance | $ 35.58 | $ 38.65
Total Return, at net asset value | (0.20%) | 2.70%
Total Return, at market value | (0.20%) | 2.70%
Ratios to Average Net Assets |  |
Expense ratio | (0.96%) | (0.96%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.91%) | (0.91%)
ProShares UltraShort Australian Dollar [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 46.6384 | $ 37.8081
Net investment income (loss) | $ (0.1073) | $ (0.0867)
Net realized and unrealized gain (loss) | $ (4.2001) | $ (0.8315)
Change in net asset value from operations | $ (4.3074) | $ (0.9182)
Net asset value, ending balance | $ 42.3310 | $ 36.8899
Market value per share, beginning balance | $ 46.66 | $ 37.74
Market value per share, ending balance | $ 42.27 | $ 36.41
Total Return, at net asset value | (9.20%) | (2.40%)
Total Return, at market value | (9.40%) | (3.50%)
Ratios to Average Net Assets |  |
Expense ratio | (1.01%) | (0.99%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.95%) | (0.94%)
ProShares UltraShort Euro [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 17.0613 | $ 19.0172
Net investment income (loss) | $ (0.0373) | $ (0.0411)
Net realized and unrealized gain (loss) | $ (0.0976) | $ 1.0374
Change in net asset value from operations | $ (0.1349) | $ 0.9963
Net asset value, ending balance | $ 16.9264 | $ 20.0135
Market value per share, beginning balance | $ 17.06 | $ 19.01
Market value per share, ending balance | $ 16.93 | $ 20.00
Total Return, at net asset value | (0.80%) | 5.20%
Total Return, at market value | (0.80%) | 5.20%
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.88%) | (0.88%)
ProShares UltraShort Yen [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 70.8640 | $ 50.7577
Net investment income (loss) | $ (0.1459) | $ (0.1244)
Net realized and unrealized gain (loss) | $ (3.1017) | $ 8.3770
Change in net asset value from operations | $ (3.2476) | $ 8.2526
Net asset value, ending balance | $ 67.6164 | $ 59.0103
Market value per share, beginning balance | $ 70.91 | $ 50.77
Market value per share, ending balance | $ 67.62 | $ 59.00
Total Return, at net asset value | (4.60%) | 16.30%
Total Return, at market value | (4.60%) | 16.20%
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.88%) | (0.88%)
ProShares Ultra DJ-UBS Commodity [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 19.4317 | $ 24.3875
Net investment income (loss) | $ (0.0464) | $ (0.0535)
Net realized and unrealized gain (loss) | $ 2.7213 | $ (0.7240)
Change in net asset value from operations | $ 2.6749 | $ (0.7775)
Net asset value, ending balance | $ 22.1066 | $ 23.6100
Market value per share, beginning balance | $ 19.13 | $ 23.93
Market value per share, ending balance | $ 21.51 | $ 23.92
Total Return, at net asset value | 13.80% | (3.20%)
Total Return, at market value | 12.40% | 0.00%
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.91%) | (0.89%)
ProShares Ultra DJ-UBS Crude Oil [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 32.0899 | $ 29.3941
Net investment income (loss) | $ (0.0712) | $ (0.0674)
Net realized and unrealized gain (loss) | $ 2.6074 | $ 2.3426
Change in net asset value from operations | $ 2.5362 | $ 2.2752
Net asset value, ending balance | $ 34.6261 | $ 31.6693
Market value per share, beginning balance | $ 32.22 | $ 29.32
Market value per share, ending balance | $ 34.56 | $ 31.56
Total Return, at net asset value | 7.90% | 7.70%
Total Return, at market value | 7.30% | 7.60%
Ratios to Average Net Assets |  |
Expense ratio | (0.98%) | (0.97%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.92%) | (0.90%)
ProShares Ultra DJ-UBS Natural Gas [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 38.8383 | $ 39.0490
Net investment income (loss) | $ (0.1183) | $ (0.1040)
Net realized and unrealized gain (loss) | $ 6.4173 | $ 11.3070
Change in net asset value from operations | $ 6.2990 | $ 11.2030
Net asset value, ending balance | $ 45.1373 | $ 50.2520
Market value per share, beginning balance | $ 39.28 | $ 39.24
Market value per share, ending balance | $ 45.32 | $ 49.95
Total Return, at net asset value | 16.20% | 28.70%
Total Return, at market value | 15.40% | 27.30%
Ratios to Average Net Assets |  |
Expense ratio | (1.11%) | (1.13%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (1.06%) | (1.06%)
ProShares Ultra Gold [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 41.2553 | $ 83.7634
Net investment income (loss) | $ (0.1060) | $ (0.1744)
Net realized and unrealized gain (loss) | $ 5.8746 | $ (6.4032)
Change in net asset value from operations | $ 5.7686 | $ (6.5776)
Net asset value, ending balance | $ 47.0239 | $ 77.1858
Market value per share, beginning balance | $ 41.26 | $ 85.34
Market value per share, ending balance | $ 46.34 | $ 77.01
Total Return, at net asset value | 14.00% | (7.90%)
Total Return, at market value | 12.30% | (9.80%)
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.91%) | (0.88%)
ProShares Ultra Silver [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 63.3305 | $ 171.8906
Net investment income (loss) | $ (0.1535) | $ (0.3644)
Net realized and unrealized gain (loss) | $ 2.0543 | $ (17.6120)
Change in net asset value from operations | $ 1.9008 | $ (17.9764)
Net asset value, ending balance | $ 65.2313 | $ 153.9142
Market value per share, beginning balance | $ 63.04 | $ 176.40
Market value per share, ending balance | $ 64.12 | $ 151.00
Total Return, at net asset value | 3.00% | (10.50%)
Total Return, at market value | 1.70% | (14.40%)
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.90%) | (0.87%)
ProShares Ultra Australian Dollar [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 31.6801 | $ 41.4986
Net investment income (loss) | $ (0.0733) | $ (0.0949)
Net realized and unrealized gain (loss) | $ 2.8368 | $ 0.7443
Change in net asset value from operations | $ 2.7635 | $ 0.6494
Net asset value, ending balance | $ 34.4436 | $ 42.1480
Market value per share, beginning balance | $ 31.61 | $ 41.45
Market value per share, ending balance | $ 34.46 | $ 42.55
Total Return, at net asset value | 8.70% | 1.60%
Total Return, at market value | 9.00% | 2.70%
Ratios to Average Net Assets |  |
Expense ratio | (1.00%) | (0.99%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.93%) | (0.92%)
ProShares Ultra Euro [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 26.0346 | $ 24.3499
Net investment income (loss) | $ (0.0566) | $ (0.0536)
Net realized and unrealized gain (loss) | $ 0.0512 | $ (1.4326)
Change in net asset value from operations | $ (0.0054) | $ (1.4862)
Net asset value, ending balance | $ 26.0292 | $ 22.8637
Market value per share, beginning balance | $ 25.98 | $ 24.32
Market value per share, ending balance | $ 25.98 | $ 22.92
Total Return, at net asset value | 0.00% | (6.10%)
Total Return, at market value | 0.00% | (5.80%)
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.89%) | (0.89%)
ProShares Ultra Yen [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 18.6318 | $ 28.1840
Net investment income (loss) | $ (0.0428) | $ (0.0537)
Net realized and unrealized gain (loss) | $ 0.7168 | $ (4.3565)
Change in net asset value from operations | $ 0.6740 | $ (4.4102)
Net asset value, ending balance | $ 19.3058 | $ 23.7738
Market value per share, beginning balance | $ 18.61 | $ 28.28
Market value per share, ending balance | $ 19.29 | $ 23.69
Total Return, at net asset value | 3.60% | (15.60%)
Total Return, at market value | 3.70% | (16.20%)
Ratios to Average Net Assets |  |
Expense ratio | (0.95%) | (0.95%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (0.89%) | (0.88%)
ProShares VIX Short-Term Futures ETF [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 28.5387 | $ 83.9374
Net investment income (loss) | $ (0.0577) | $ (0.1201)
Net realized and unrealized gain (loss) | $ (0.2803) | $ (29.6940)
Change in net asset value from operations | $ (0.3380) | $ (29.8141)
Net asset value, ending balance | $ 28.2007 | $ 54.1233
Market value per share, beginning balance | $ 28.53 | $ 85.05
Market value per share, ending balance | $ 28.10 | $ 54.50
Total Return, at net asset value | (1.20%) | (35.50%)
Total Return, at market value | (1.50%) | (35.90%)
Ratios to Average Net Assets |  |
Expense ratio | (0.85%) | (0.85%)
Expense ratio, excluding brokerage commissions | (0.85%) | (0.85%)
Net investment income (loss) | (0.80%) | (0.79%)
ProShares VIX Mid-Term Futures ETF [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 19.2959 | $ 34.7003
Net investment income (loss) | $ (0.0383) | $ (0.0539)
Net realized and unrealized gain (loss) | $ (0.7639) | $ (8.2105)
Change in net asset value from operations | $ (0.8022) | $ (8.2644)
Net asset value, ending balance | $ 18.4937 | $ 26.4359
Market value per share, beginning balance | $ 19.29 | $ 34.22
Market value per share, ending balance | $ 18.50 | $ 26.43
Total Return, at net asset value | (4.20%) | (23.80%)
Total Return, at market value | (4.10%) | (22.80%)
Ratios to Average Net Assets |  |
Expense ratio | (0.85%) | (0.85%)
Expense ratio, excluding brokerage commissions | (0.85%) | (0.85%)
Net investment income (loss) | (0.81%) | (0.79%)
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 67.0841 | $ 805.2711
Net investment income (loss) | $ (0.2919) | $ (1.8551)
Net realized and unrealized gain (loss) | $ (6.4957) | $ (500.3708)
Change in net asset value from operations | $ (6.7876) | $ (502.2259)
Net asset value, ending balance | $ 60.2965 | $ 303.0453
Market value per share, beginning balance | $ 67.12 | $ 836.00
Market value per share, ending balance | $ 59.91 | $ 307.60
Total Return, at net asset value | (10.10%) | (62.40%)
Total Return, at market value | (10.70%) | (63.20%)
Ratios to Average Net Assets |  |
Expense ratio | (1.79%) | (1.94%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (1.76%) | (1.91%)
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Financial Highlights [Line Items] |  |
Net asset value, beginning balance | $ 67.4993 | $ 33.0649
Net investment income (loss) | $ (0.2209) | $ (0.1506)
Net realized and unrealized gain (loss) | $ (5.4192) | $ 13.1843
Change in net asset value from operations | $ (5.6401) | $ 13.0337
Net asset value, ending balance | $ 61.8592 | $ 46.0986
Market value per share, beginning balance | $ 67.47 | $ 32.73
Market value per share, ending balance | $ 61.97 | $ 45.54
Total Return, at net asset value | (8.40%) | 39.40%
Total Return, at market value | (8.20%) | 39.20%
Ratios to Average Net Assets |  |
Expense ratio | (1.50%) | (1.54%)
Expense ratio, excluding brokerage commissions | (0.95%) | (0.95%)
Net investment income (loss) | (1.45%) | (1.47%)

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