v3.10.0.1

Schedule of Investments - Short-Term U.S. Government and Agency Obligations (Parenthetical) (Detail) - USD ($) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2018 | Dec. 31, 2017
Schedule of Investments [Line Items] |  |  |
Total short-term U.S. government and agency obligations, cost |  | $ 1,300,321,650 | $ 2,445,970,899
ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 68.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 5,686,543 | 6,996,595
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 |  | 18.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 92,995,995 | 494,962,509
ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 80.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 365,929,311 | 459,543,053
ProShares Ultra Bloomberg Natural Gas [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 |  | $ 17,958,439 | 50,963,586
ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 37.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 3,288,832 | 6,996,595
ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 107.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 87,844,378 | 88,890,367
ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 102.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 212,497,644 | 235,605,469
ProShares Ultra Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 35.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 997,983 | 1,998,216
ProShares UltraShort Australian Dollar [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 |  | $ 4,988,035 | 11,984,898
ProShares UltraShort Bloomberg Crude Oil [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 |  | $ 173,645,496 | 253,669,155
ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 61.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 4,092,929 | 3,999,667
ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 80.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 141,643,132 | 204,788,208
ProShares UltraShort Gold [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 |  | $ 22,952,432 | 31,979,626
ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 86.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 19,971,100 | 18,352,808
ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 96.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 80,832,200 | 131,844,652
ProShares VIX Short-Term Futures ETF [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity |  | 19.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 21,999,053 | 134,855,770
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 |  | 12.00% |
Total short-term U.S. government and agency obligations, cost |  | $ 42,998,148 | $ 287,546,397
U.S Treasury Bills 1.771% due 07/19/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.771% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S Treasury Bills 1.771% due 07/19/18 [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.771% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.831% |
Debt instrument, maturity date | [1],[2] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.831% |
Debt instrument, maturity date | [1],[3] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.831% due 08/02/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.871% |
Debt instrument, maturity date | [1],[3] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.871% |
Debt instrument, maturity date | [1],[2] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares Ultra Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.871% |
Debt instrument, maturity date | [1],[3] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.871% |
Debt instrument, maturity date | [1],[3] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.871% |
Debt instrument, maturity date | [1],[3] | Aug. 09, 2018 |
U.S. Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.907% |
Debt instrument, maturity date | [1] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.907% |
Debt instrument, maturity date | [1] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.907% |
Debt instrument, maturity date | [1],[2] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.907% |
Debt instrument, maturity date | [1],[2] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.907% |
Debt instrument, maturity date | [1],[3] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.907% |
Debt instrument, maturity date | [1] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.907% |
Debt instrument, maturity date | [1],[3] | Aug. 30, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.907% |
Debt instrument, maturity date | [1],[3] | Aug. 30, 2018 |
U.S. Treasury Bills 1.886% due 09/13/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.886% |
Debt instrument, maturity date | [1] | Sep. 13, 2018 |
U.S. Treasury Bills 1.886% due 09/13/18 [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.886% |
Debt instrument, maturity date | [1],[3] | Sep. 13, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.934% |
Debt instrument, maturity date | [1] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.934% |
Debt instrument, maturity date | [1],[3] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.934% |
Debt instrument, maturity date | [1] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.934% |
Debt instrument, maturity date | [1],[2] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 193.40% |
Debt instrument, maturity date | [1],[2] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.934% |
Debt instrument, maturity date | [1] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.934% |
Debt instrument, maturity date | [1],[3] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.934% |
Debt instrument, maturity date | [1] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.934% |
Debt instrument, maturity date | [1],[4] | Oct. 11, 2018 |
U.S. Treasury Bills 1.934% due 10/11/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.934% |
Debt instrument, maturity date | [1],[4] | Oct. 11, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares Short Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.99% |
Debt instrument, maturity date | [1] | Nov. 08, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.99% |
Debt instrument, maturity date | [1],[3] | Nov. 08, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.99% |
Debt instrument, maturity date | [1] | Nov. 08, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.99% |
Debt instrument, maturity date | [1],[2] | Nov. 08, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.99% |
Debt instrument, maturity date | [1],[2] | Nov. 08, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.99% |
Debt instrument, maturity date | [1] | Nov. 08, 2018 |
U.S. Treasury Bills 1.990% due 11/08/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.99% |
Debt instrument, maturity date | [1],[3] | Nov. 08, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | 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 | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | ProShares VIX Short-Term Futures ETF [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
U.S. Treasury Bills 1.741% due 07/05/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.741% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.741% due 07/05/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.741% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.741% due 07/05/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.741% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.741% due 07/05/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.741% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.741% due 07/05/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.741% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.741% due 07/05/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.741% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.787% due 07/19/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.787% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.884% |
Debt instrument, maturity date | [1] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.884% |
Debt instrument, maturity date | [1] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.884% |
Debt instrument, maturity date | [1],[2] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.884% |
Debt instrument, maturity date | [1],[2] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.884% |
Debt instrument, maturity date | [1],[4] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.884% |
Debt instrument, maturity date | [1] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.884% |
Debt instrument, maturity date | [1],[3] | Aug. 16, 2018 |
U.S. Treasury Bills 1.884% due 08/16/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.884% |
Debt instrument, maturity date | [1],[4] | Aug. 16, 2018 |
U.S. Treasury Bills 1.907% due 08/30/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.907% |
Debt instrument, maturity date | [1],[3] | Aug. 30, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.888% |
Debt instrument, maturity date | [1],[3] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.888% |
Debt instrument, maturity date | [1] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.888% |
Debt instrument, maturity date | [1],[2] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.888% |
Debt instrument, maturity date | [1],[2] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.888% |
Debt instrument, maturity date | [1] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.888% |
Debt instrument, maturity date | [1],[3] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.888% |
Debt instrument, maturity date | [1] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.888% |
Debt instrument, maturity date | [1],[4] | Sep. 13, 2018 |
U.S. Treasury Bills 1.888% due 09/13/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.888% |
Debt instrument, maturity date | [1],[4] | Sep. 13, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.895% |
Debt instrument, maturity date | [1] | Sep. 27, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.895% |
Debt instrument, maturity date | [1] | Sep. 27, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.895% |
Debt instrument, maturity date | [1],[2] | Sep. 27, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.895% |
Debt instrument, maturity date | [1],[2] | Sep. 18, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.895% |
Debt instrument, maturity date | [1] | Sep. 27, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.895% |
Debt instrument, maturity date | [1],[3] | Sep. 27, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.895% |
Debt instrument, maturity date | [1] | Sep. 27, 2018 |
U.S. Treasury Bills 1.895% due 09/27/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.895% |
Debt instrument, maturity date | [1],[4] | Sep. 27, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.946% |
Debt instrument, maturity date | [1] | Oct. 25, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.946% |
Debt instrument, maturity date | [1] | Oct. 25, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 1.946% |
Debt instrument, maturity date | [1],[2] | Oct. 25, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 194.60% |
Debt instrument, maturity date | [1],[2] | Oct. 25, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.946% |
Debt instrument, maturity date | [1] | Oct. 25, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.946% |
Debt instrument, maturity date | [1],[3] | Oct. 25, 2018 |
U.S. Treasury Bills 1.946% due 10/25/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 1.946% |
Debt instrument, maturity date | [1],[4] | Oct. 25, 2018 |
U.S. Treasury Bills 2.036% due 11/23/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.036% |
Debt instrument, maturity date | [1] | Nov. 23, 2018 |
U.S. Treasury Bills 2.036% due 11/23/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.036% |
Debt instrument, maturity date | [1] | Nov. 23, 2018 |
U.S. Treasury Bills 2.036% due 11/23/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 2.036% |
Debt instrument, maturity date | [1],[2] | Nov. 23, 2018 |
U.S. Treasury Bills 2.036% due 11/23/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.036% |
Debt instrument, maturity date | [1] | Nov. 23, 2018 |
U.S. Treasury Bills 2.036% due 11/23/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.036% |
Debt instrument, maturity date | [1] | Nov. 23, 2018 |
U.S. Treasury Bills 2.036% due 11/23/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.036% |
Debt instrument, maturity date | [1] | Nov. 23, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 2.049% |
Debt instrument, maturity date | [1],[3] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 2.049% |
Debt instrument, maturity date | [1],[2] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.049% |
Debt instrument, maturity date | [1] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 2.049% |
Debt instrument, maturity date | [1],[3] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.049% |
Debt instrument, maturity date | [1] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 2.049% |
Debt instrument, maturity date | [1],[4] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 2.049% |
Debt instrument, maturity date | [1],[4] | Dec. 06, 2018 |
U.S. Treasury Bills 1.890% due 09/13/18 [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.89% |
Debt instrument, maturity date | [1] | Sep. 13, 2018 |
U.S. Treasury Bills 1.890% due 09/13/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 1.89% |
Debt instrument, maturity date | [1],[3] | Sep. 13, 2018 |
United States Treasury Bills One Point Seven Three Seven Percentage Due July Five Two Thousand And Eighteen [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.737% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
U.S. Treasury Bills 1.795% due 07/19/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.795% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares Ultra Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 2.049% |
Debt instrument, maturity date | [1] | Dec. 06, 2018 |
U.S. Treasury Bills 2.049% due 12/06/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[2] | 2.049% |
Debt instrument, maturity date | [1],[2] | Dec. 06, 2018 |
U.S. Treasury Bills 1.783% due 07/19/18 [Member] | ProShares Ultra Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.783% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S. Treasury Bills 1.783% due 07/19/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.783% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S. Treasury Bills 1.785% due 07/19/18 [Member] | ProShares Ultra Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.785% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
U.S. Treasury Bills 1.785% due 07/19/18 [Member] | ProShares UltraShort Euro [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.785% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
US Treasury Bills 1.737% due 07/05/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.737% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
US Treasury Bills 1.737% due 07/05/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.737% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
US Treasury Bills 1.737% due 07/05/18 [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.737% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
United States Treasury Bills 1.792% due 07/19/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.792% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
US Treasury Bills 1.831% due 08/02/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
US Treasury Bills 1.831% due 08/02/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.831% |
Debt instrument, maturity date | [1] | Aug. 02, 2018 |
US Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
US Treasury Bills 1.871% due 08/09/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.871% |
Debt instrument, maturity date | [1] | Aug. 09, 2018 |
US Treasury Bills 1.907% due 08/30/18 [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.907% |
Debt instrument, maturity date | [1] | Aug. 30, 2018 |
US Treasury Bills 1.907% due 08/30/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.907% |
Debt instrument, maturity date | [1] | Aug. 30, 2018 |
United States Treasury Bills 1.786% due 07/19/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.786% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
United States Treasury Bills 2.036% due 11/23/18 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[3] | 2.036% |
Debt instrument, maturity date | [1],[3] | Nov. 23, 2018 |
United States Treasury Bills 2.036% due 11/23/18 [Member] | ProShares UltraShort Yen [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1],[4] | 2.036% |
Debt instrument, maturity date | [1],[4] | Nov. 23, 2018 |
US Treasury Bills 1.799% due 07/19/18 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.799% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
US Treasury Bills 1.743% due 07/05/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.743% |
Debt instrument, maturity date | [1] | Jul. 05, 2018 |
US Treasury Bills 1.771% due 07/19/18 [Member] | ProShares UltraShort Silver [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 1.771% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
Federal Home Loan Discount Notes 1.551% due 07/02/18 [Member] | 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 | [1] | 1.551% |
Debt instrument, maturity date | [1] | Jul. 02, 2018 |
US Treasury Bills One Point Seven Nine Five Percentage Due July Nineteen Two Thousand and Eighteen [Member] | ProShares UltraShort Gold [Member] |  |  |
Schedule of Investments [Line Items] |  |  |
Short-term U.S. government and agency obligations percentage of shareholders' equity | [1] | 0.01792% |
Debt instrument, maturity date | [1] | Jul. 19, 2018 |
[1] | Rates shown represent discount rate at the time of purchase.
[2] | All or partial amount pledged as collateral for forward agreements.
[3] | All or partial amount pledged as collateral for swap agreements.
[4] | All or partial amount pledged as collateral for foreign currency forward contracts.

X
- Definition Short-term U.S. government and agency obligations, cost. + References No definition available. + Details
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- Definition Short term US government and agency obligations of shareholders equity. + References No definition available. + Details
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- Definition The maturity date of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 12 -Sentence Column A + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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