v2.4.0.6

Financial Highlights - Per Share Operating Performance (Detail) (USD $) | 3 Months Ended
--- | ---
Mar. 31, 2013 | Mar. 31, 2012
ProShares UltraShort DJ-UBS Commodity [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 54.10 |  | $ 56.9207 |
Net investment income (loss) | $ (0.1143) |  | $ (0.1219) |
Net realized and unrealized gain (loss) | $ 1.1149 |  | $ (1.7902) |
Change in net asset value from operations | $ 1.0006 |  | $ (1.9121) |
Net asset value, ending balance | $ 55.10 |  | $ 55.0086 |
Market value per share, beginning balance | $ 51.64 | [1] | $ 56.19 | [1]
Market value per share, ending balance | $ 51.14 | [1] | $ 54.71 | [1]
Total Return, at net asset value | 1.80% | [2] | (3.40%) | [3]
Total Return, at market value | (1.00%) | [2] | (2.60%) | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.95%) |  | (0.95%) |
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) |
Net investment income (loss) | (0.86%) |  | (0.92%) |
ProShares UltraShort DJ-UBS Crude Oil [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 40.31 |  | $ 38.8151 |
Net investment income (loss) | $ (0.0850) |  | $ (0.0823) |
Net realized and unrealized gain (loss) | $ (3.7437) |  | $ (3.4880) |
Change in net asset value from operations | $ (3.8287) |  | $ (3.5703) |
Net asset value, ending balance | $ 36.48 |  | $ 35.2448 |
Market value per share, beginning balance | $ 40.44 | [1] | $ 38.69 | [1]
Market value per share, ending balance | $ 36.62 | [1] | $ 35.16 | [1]
Total Return, at net asset value | (9.50%) | [2] | (9.20%) | [3]
Total Return, at market value | (9.40%) | [2] | (9.10%) | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.97%) |  | (0.97%) |
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) |
Net investment income (loss) | (0.90%) |  | (0.94%) |
ProShares UltraShort DJ-UBS Natural Gas [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 25.54 |  | $ 23.8053 | [4]
Net investment income (loss) | $ (0.0641) |  | $ (0.1081) | [4]
Net realized and unrealized gain (loss) | $ (7.5049) |  | $ 25.2447 | [4]
Change in net asset value from operations | $ (7.5690) |  | $ 25.1366 | [4]
Net asset value, ending balance | $ 17.97 |  | $ 48.9419 | [4]
Market value per share, beginning balance | $ 25.41 | [1] | $ 23.96 | [1],[4]
Market value per share, ending balance | $ 18.06 | [1] | $ 49.35 | [1],[4]
Total Return, at net asset value | (29.60%) | [2] | 105.60% | [3],[4]
Total Return, at market value | (28.90%) | [2] | 106.00% | [3],[4]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (1.21%) |  | (1.36%) | [4]
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) | [4]
Net investment income (loss) | (1.15%) |  | (1.34%) | [4]
ProShares UltraShort Gold [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 63.87 |  | $ 82.7114 | [4]
Net investment income (loss) | $ (0.1428) |  | $ (0.1556) | [4]
Net realized and unrealized gain (loss) | $ 4.1421 |  | $ (14.8151) | [4]
Change in net asset value from operations | $ 3.9993 |  | $ (14.9707) | [4]
Net asset value, ending balance | $ 67.87 |  | $ 67.7407 | [4]
Market value per share, beginning balance | $ 62.60 | [1] | $ 79.24 | [1],[4]
Market value per share, ending balance | $ 68.01 | [1] | $ 67.24 | [1],[4]
Total Return, at net asset value | 6.30% | [2] | (18.10%) | [3],[4]
Total Return, at market value | 8.60% | [2] | (15.10%) | [3],[4]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.95%) |  | (0.95%) | [4]
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) | [4]
Net investment income (loss) | (0.88%) |  | (0.93%) | [4]
ProShares UltraShort Silver [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 51.40 |  | $ 76.6771 |
Net investment income (loss) | $ (0.1068) |  | $ (0.1245) |
Net realized and unrealized gain (loss) | $ 2.7733 |  | $ (24.1170) |
Change in net asset value from operations | $ 2.6665 |  | $ (24.2415) |
Net asset value, ending balance | $ 54.06 |  | $ 52.4356 |
Market value per share, beginning balance | $ 50.07 | [1] | $ 79.35 | [1]
Market value per share, ending balance | $ 55.02 | [1] | $ 52.75 | [1]
Total Return, at net asset value | 5.20% | [2] | (31.60%) | [3]
Total Return, at market value | 9.90% | [2] | (33.50%) | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.95%) |  | (0.95%) |
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) |
Net investment income (loss) | (0.87%) |  | (0.92%) |
ProShares Short Euro [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 37.63 |  |  |
Net investment income (loss) | $ (0.0840) |  |  |
Net realized and unrealized gain (loss) | $ 1.0874 |  |  |
Change in net asset value from operations | $ 1.0034 |  |  |
Net asset value, ending balance | $ 38.63 |  |  |
Market value per share, beginning balance | $ 37.64 | [1] |  |
Market value per share, ending balance | $ 38.65 | [1] |  |
Total Return, at net asset value | 2.70% | [2] |  |
Total Return, at market value | 2.70% | [2] |  |
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.96%) |  |  |
Expense ratio, excluding brokerage commissions | (0.95%) |  |  |
Net investment income (loss) | (0.91%) |  |  |
ProShares UltraShort Australian Dollar [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 37.81 |  |  |
Net investment income (loss) | $ (0.0867) |  |  |
Net realized and unrealized gain (loss) | $ (0.8315) |  |  |
Change in net asset value from operations | $ (0.9182) |  |  |
Net asset value, ending balance | $ 36.89 |  |  |
Market value per share, beginning balance | $ 37.74 | [1] |  |
Market value per share, ending balance | $ 36.41 | [1] |  |
Total Return, at net asset value | (2.40%) | [2] |  |
Total Return, at market value | (3.50%) | [2] |  |
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.99%) |  |  |
Expense ratio, excluding brokerage commissions | (0.95%) |  |  |
Net investment income (loss) | (0.94%) |  |  |
ProShares UltraShort Euro [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 19.02 |  | $ 20.3357 |
Net investment income (loss) | $ (0.0411) |  | $ (0.0457) |
Net realized and unrealized gain (loss) | $ 1.0374 |  | $ (1.3187) |
Change in net asset value from operations | $ 0.9963 |  | $ (1.3644) |
Net asset value, ending balance | $ 20.01 |  | $ 18.9713 |
Market value per share, beginning balance | $ 19.01 | [1] | $ 20.35 | [1]
Market value per share, ending balance | $ 20.00 | [1] | $ 18.97 | [1]
Total Return, at net asset value | 5.20% | [2] | (6.70%) | [3]
Total Return, at market value | 5.20% | [2] | (6.80%) | [3]
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%) |  | (0.93%) |
ProShares UltraShort Yen [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 50.76 |  | $ 40.9557 |
Net investment income (loss) | $ (0.1244) |  | $ (0.0990) |
Net realized and unrealized gain (loss) | $ 8.3770 |  | $ 6.1883 |
Change in net asset value from operations | $ 8.2526 |  | $ 6.0893 |
Net asset value, ending balance | $ 59.01 |  | $ 47.0450 |
Market value per share, beginning balance | $ 50.77 | [1] | $ 40.95 | [1]
Market value per share, ending balance | $ 59.00 | [1] | $ 47.05 | [1]
Total Return, at net asset value | 16.30% | [2] | 14.90% | [3]
Total Return, at market value | 16.20% | [2] | 14.90% | [3]
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%) |  | (0.92%) |
ProShares Ultra DJ-UBS Commodity [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 24.39 |  | $ 25.8805 |
Net investment income (loss) | $ (0.0535) |  | $ (0.0629) |
Net realized and unrealized gain (loss) | $ (0.7240) |  | $ 0.2837 |
Change in net asset value from operations | $ (0.7775) |  | $ 0.2208 |
Net asset value, ending balance | $ 23.61 |  | $ 26.1013 |
Market value per share, beginning balance | $ 23.93 | [1] | $ 25.64 | [1]
Market value per share, ending balance | $ 23.92 | [1] | $ 25.90 | [1]
Total Return, at net asset value | (3.20%) | [2] | 0.90% | [3]
Total Return, at market value | 0.00% | [2] | 1.00% | [3]
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%) |  | (0.93%) |
ProShares Ultra DJ-UBS Crude Oil [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 29.39 |  | $ 40.8828 |
Net investment income (loss) | $ (0.0674) |  | $ (0.1023) |
Net realized and unrealized gain (loss) | $ 2.3426 |  | $ 2.0318 |
Change in net asset value from operations | $ 2.2752 |  | $ 1.9295 |
Net asset value, ending balance | $ 31.67 |  | $ 42.8123 |
Market value per share, beginning balance | $ 29.32 | [1] | $ 40.94 | [1]
Market value per share, ending balance | $ 31.56 | [1] | $ 42.91 | [1]
Total Return, at net asset value | 7.70% | [2] | 4.70% | [3]
Total Return, at market value | 7.60% | [2] | 4.80% | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.97%) |  | (0.96%) |
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) |
Net investment income (loss) | (0.90%) |  | (0.94%) |
ProShares Ultra DJ-UBS Natural Gas [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 39.05 |  | $ 101.9786 | [4]
Net investment income (loss) | $ (0.1040) |  | $ (0.1657) | [4]
Net realized and unrealized gain (loss) | $ 11.3070 |  | $ (64.1194) | [4]
Change in net asset value from operations | $ 11.2030 |  | $ (64.2851) | [4]
Net asset value, ending balance | $ 50.25 |  | $ 37.6935 | [4]
Market value per share, beginning balance | $ 39.24 | [1] | $ 101.35 | [1],[4]
Market value per share, ending balance | $ 49.95 | [1] | $ 37.40 | [1],[4]
Total Return, at net asset value | 28.70% | [2] | (63.00%) | [3],[4]
Total Return, at market value | 27.30% | [2] | (63.10%) | [3],[4]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (1.13%) |  | (1.23%) | [4]
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) | [4]
Net investment income (loss) | (1.06%) |  | (1.20%) | [4]
ProShares Ultra Gold [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 83.76 |  | $ 75.9066 |
Net investment income (loss) | $ (0.1744) |  | $ (0.2085) |
Net realized and unrealized gain (loss) | $ (6.4032) |  | $ 12.0919 |
Change in net asset value from operations | $ (6.5776) |  | $ 11.8834 |
Net asset value, ending balance | $ 77.19 |  | $ 87.7900 |
Market value per share, beginning balance | $ 85.34 | [1] | $ 79.01 | [1]
Market value per share, ending balance | $ 77.01 | [1] | $ 88.40 | [1]
Total Return, at net asset value | (7.90%) | [2] | 15.70% | [3]
Total Return, at market value | (9.80%) | [2] | 11.90% | [3]
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%) |  | (0.92%) |
ProShares Ultra Silver [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 42.97 |  | $ 43.1903 |
Net investment income (loss) | $ (0.0911) |  | $ (0.1297) |
Net realized and unrealized gain (loss) | $ (4.4031) |  | $ 11.8333 |
Change in net asset value from operations | $ (4.4942) |  | $ 11.7036 |
Net asset value, ending balance | $ 38.48 |  | $ 54.8939 |
Market value per share, beginning balance | $ 44.10 | [1] | $ 41.65 | [1]
Market value per share, ending balance | $ 37.75 | [1] | $ 54.46 | [1]
Total Return, at net asset value | (10.50%) | [2] | 27.10% | [3]
Total Return, at market value | (14.40%) | [2] | 30.80% | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.95%) |  | (0.95%) |
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) |
Net investment income (loss) | (0.87%) |  | (0.92%) |
ProShares Ultra Australian Dollar [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 41.50 |  |  |
Net investment income (loss) | $ (0.0949) |  |  |
Net realized and unrealized gain (loss) | $ 0.7443 |  |  |
Change in net asset value from operations | $ 0.6494 |  |  |
Net asset value, ending balance | $ 42.15 |  |  |
Market value per share, beginning balance | $ 41.45 | [1] |  |
Market value per share, ending balance | $ 42.55 | [1] |  |
Total Return, at net asset value | 1.60% | [2] |  |
Total Return, at market value | 2.70% | [2] |  |
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.99%) |  |  |
Expense ratio, excluding brokerage commissions | (0.95%) |  |  |
Net investment income (loss) | (0.92%) |  |  |
ProShares Ultra Euro [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 24.35 |  | $ 23.8860 |
Net investment income (loss) | $ (0.0536) |  | $ (0.0565) |
Net realized and unrealized gain (loss) | $ (1.4326) |  | $ 1.4163 |
Change in net asset value from operations | $ (1.4862) |  | $ 1.3598 |
Net asset value, ending balance | $ 22.86 |  | $ 25.2458 |
Market value per share, beginning balance | $ 24.32 | [1] | $ 23.87 | [1]
Market value per share, ending balance | $ 22.92 | [1] | $ 25.21 | [1]
Total Return, at net asset value | (6.10%) | [2] | 5.70% | [3]
Total Return, at market value | (5.80%) | [2] | 5.60% | [3]
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%) |  | (0.93%) |
ProShares Ultra Yen [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 28.18 |  | $ 36.4704 |
Net investment income (loss) | $ (0.0537) |  | $ (0.0787) |
Net realized and unrealized gain (loss) | $ (4.3565) |  | $ (5.0241) |
Change in net asset value from operations | $ (4.4102) |  | $ (5.1028) |
Net asset value, ending balance | $ 23.77 |  | $ 31.3676 |
Market value per share, beginning balance | $ 28.28 | [1] | $ 36.50 | [1]
Market value per share, ending balance | $ 23.69 | [1] | $ 31.36 | [1]
Total Return, at net asset value | (15.60%) | [2] | (14.00%) | [3]
Total Return, at market value | (16.20%) | [2] | (14.10%) | [3]
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%) |  | (0.92%) |
ProShares VIX Short-Term Futures ETF [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 16.79 |  | $ 76.3738 |
Net investment income (loss) | $ (0.0240) |  | $ (0.0979) |
Net realized and unrealized gain (loss) | $ (5.9388) |  | $ (40.7796) |
Change in net asset value from operations | $ (5.9628) |  | $ (40.8775) |
Net asset value, ending balance | $ 10.82 |  | $ 35.4963 |
Market value per share, beginning balance | $ 17.01 | [1] | $ 75.74 | [1]
Market value per share, ending balance | $ 10.90 | [1] | $ 35.77 | [1]
Total Return, at net asset value | (35.50%) | [2] | (53.50%) | [3]
Total Return, at market value | (35.90%) | [2] | (52.80%) | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.85%) |  | (0.85%) |
Expense ratio, excluding brokerage commissions | (0.85%) |  | (0.85%) |
Net investment income (loss) | (0.79%) |  | (0.81%) |
ProShares VIX Mid-Term Futures ETF [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 34.70 |  | $ 74.1396 |
Net investment income (loss) | $ (0.0539) |  | $ (0.1356) |
Net realized and unrealized gain (loss) | $ (8.2105) |  | $ (18.0538) |
Change in net asset value from operations | $ (8.2644) |  | $ (18.1894) |
Net asset value, ending balance | $ 26.44 |  | $ 55.9502 |
Market value per share, beginning balance | $ 34.22 | [1] | $ 74.13 | [1]
Market value per share, ending balance | $ 26.43 | [1] | $ 56.74 | [1]
Total Return, at net asset value | (23.80%) | [2] | (24.50%) | [3]
Total Return, at market value | (22.80%) | [2] | (23.50%) | [3]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (0.85%) |  | (0.85%) |
Expense ratio, excluding brokerage commissions | (0.85%) |  | (0.85%) |
Net investment income (loss) | (0.79%) |  | (0.83%) |
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 20.13 |  | $ 741.0464 | [4]
Net investment income (loss) | $ (0.0464) |  | $ (1.2046) | [4]
Net realized and unrealized gain (loss) | $ (12.5093) |  | $ (596.8653) | [4]
Change in net asset value from operations | $ (12.5557) |  | $ (598.0699) | [4]
Net asset value, ending balance | $ 7.58 |  | $ 142.9765 | [4]
Market value per share, beginning balance | $ 20.90 | [1] | $ 729.60 | [1],[4]
Market value per share, ending balance | $ 7.69 | [1] | $ 145.60 | [1],[4]
Total Return, at net asset value | (62.40%) | [2] | (80.70%) | [3],[4]
Total Return, at market value | (63.20%) | [2] | (80.00%) | [3],[4]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (1.94%) |  | (2.02%) | [4]
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) | [4]
Net investment income (loss) | (1.91%) |  | (2.01%) | [4]
ProShares Short VIX Short-Term Futures ETF [Member] |  |  |  |
Financial Highlights [Line Items] |  |  |  |
Net asset value, beginning balance | $ 66.13 |  | $ 25.8664 | [4]
Net investment income (loss) | $ (0.3013) |  | $ (0.1788) | [4]
Net realized and unrealized gain (loss) | $ 26.3688 |  | $ 23.7982 | [4]
Change in net asset value from operations | $ 26.0675 |  | $ 23.6194 | [4]
Net asset value, ending balance | $ 92.20 |  | $ 49.4858 | [4]
Market value per share, beginning balance | $ 65.45 | [1] | $ 26.14 | [1],[4]
Market value per share, ending balance | $ 91.08 | [1] | $ 49.07 | [1],[4]
Total Return, at net asset value | 39.40% | [2] | 91.30% | [3],[4]
Total Return, at market value | 39.20% | [2] | 87.70% | [3],[4]
Ratios to Average Net Assets |  |  |  |
Expense ratio | (1.54%) |  | (2.00%) | [4]
Expense ratio, excluding brokerage commissions | (0.95%) |  | (0.95%) | [4]
Net investment income (loss) | (1.47%) |  | (1.97%) | [4]
[1] | Market values are determined at the close of the New York Stock Exchange, which may be later than when the Funds' net asset value is calculated.
[2] | Percentages are not annualized for the period ended March 31, 2013.
[3] | Percentages are not annualized for the period ended March 31, 2012.
[4] | See Note 1 of these Notes to Financial Statements.

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- Definition Market value per share + References No definition available. + Details
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- Definition Net asset value per share + References No definition available. + Details
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- Definition Net Investment Income (Loss) Ratio to Average Net Assets + References No definition available. + Details
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- Definition Net Realized and Unrealized Gain (loss), Per Share + References No definition available. + Details
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Namespace Prefix: | ck0001415311_
Data Type: | num:perShareItemType
Balance Type: | na
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- Details
Name: | ck0001415311_RatiosToAverageNetAssetsAbstract
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Data Type: | xbrli:stringItemType
Balance Type: | na
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- Definition Total Return, at Market Value, Per Share + References No definition available. + Details
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Data Type: | num:percentItemType
Balance Type: | na
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- Definition Total Return, at Net Asset value, Per Share + References No definition available. + Details
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Namespace Prefix: | ck0001415311_
Data Type: | num:percentItemType
Balance Type: | na
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