v3.10.0.1

Schedule of Investments - Foreign Currency Forward Contracts (Detail) | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2018 USD ($) | Jun. 30, 2018 EUR (€) | Dec. 31, 2017 USD ($)
Schedule of Investments [Line Items] |  |  |  |
Total Unrealized Appreciation |  | $ 83,731,789 |  | $ 62,238,361
ProShares Ultra Euro [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Total Unrealized Appreciation |  | (172,054) |  |
ProShares Ultra Euro [Member] | Contracts to Purchase [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Unrealized Appreciation (Depreciation) | [1] | $ (169,032) |  |
ProShares Ultra Euro [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (77,986) |  |
ProShares Ultra Euro [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (91,046) |  |
ProShares Ultra Euro [Member] | Contracts to Sell [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Unrealized Appreciation (Depreciation) | [1] | $ (3,022) |  |
ProShares Ultra Euro [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (3,022) |  |
ProShares Ultra Euro [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | € | [1] |  | € 7,275,525 |
ProShares Ultra Euro [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | € | [1] |  | 8,350,300 |
ProShares Ultra Euro [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | € | [1] |  | (487,200) |
ProShares Ultra Euro [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 8,579,954 |  |
ProShares Ultra Euro [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 9,848,965 |  |
ProShares Ultra Euro [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (566,306) |  |
ProShares Ultra Yen [Member] | Contracts to Purchase [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Total Unrealized Depreciation | [1] | $ (24,570) |  |
ProShares Ultra Yen [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (11,895) |  |
ProShares Ultra Yen [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (12,675) |  |
ProShares Ultra Yen [Member] | Contracts to Sell [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Total Unrealized Depreciation | [1] | $ 311 |  |
ProShares Ultra Yen [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ 10 |  |
ProShares Ultra Yen [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ 301 |  |
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 324,525,000 |  |
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 325,871,400 |  |
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (2,934,400) |  |
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (7,607,800) |  |
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 2,944,608 |  |
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 2,957,555 |  |
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (26,527) |  |
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (69,053) |  |
ProShares UltraShort Euro [Member] | Contracts to Purchase [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Unrealized Appreciation (Depreciation) | [1] | $ 102,266 |  |
ProShares UltraShort Euro [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Contract Amount/ Notional Amount | [1] | $ 16,184,300 | 13,852,100 |
Unrealized Appreciation (Depreciation) | [1] | $ 2,863 |  |
ProShares UltraShort Euro [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Contract Amount/ Notional Amount | [1] | $ 38,919,886 | 33,390,600 |
Unrealized Appreciation (Depreciation) | [1] | 99,403 |  |
ProShares UltraShort Euro [Member] | Contracts to Sell [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Unrealized Appreciation (Depreciation) | [1] | $ 3,297,684 |  |
ProShares UltraShort Euro [Member] | Contracts to Sell [Member] | Euro with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Contract Amount/ Notional Amount | [1] | $ (190,507,072) | (161,505,525) |
Unrealized Appreciation (Depreciation) | [1] | $ 1,776,391 |  |
ProShares UltraShort Euro [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Contract Amount/ Notional Amount | [1] | $ (223,733,024) | € (190,156,800) |
Unrealized Appreciation (Depreciation) | [1] | 1,521,293 |  |
ProShares UltraShort Yen [Member] | Contracts to Purchase [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Unrealized Appreciation (Depreciation) | [1] | $ (57,960) |  |
ProShares UltraShort Yen [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (7,876) |  |
ProShares UltraShort Yen [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ (50,084) |  |
ProShares UltraShort Yen [Member] | Contracts to Sell [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Unrealized Appreciation (Depreciation) | [1] | $ 751,278 |  |
ProShares UltraShort Yen [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ 356,039 |  |
ProShares UltraShort Yen [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Settlement Date | [1] | Jul. 13, 2018 |  |
Unrealized Appreciation (Depreciation) | [1] | $ 395,239 |  |
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 194,370,200 |  |
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 1,202,284,300 |  |
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (9,819,252,600) |  |
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (10,284,615,200) |  |
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 1,764,388 |  |
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | 10,915,053 |  |
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | (89,092,026) |  |
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member] |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Contract Amount/ Notional Amount | [1] | $ (93,336,679) |  |
[1] | The positions and counterparties herein are as of June 30, 2018. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.

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