v3.8.0.1

Creation and Redemption of Creation Units - Schedule of Transaction Fees (Detail) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2017
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | $ 995,227 | $ 2,516,552
ProShares VIX Short-Term Futures ETF [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 49,381 | 115,876
ProShares VIX Mid-Term Futures ETF [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 5,298 | 8,510
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 337,623 | 763,477
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 385,071 | 837,558
ProShares UltraShort Bloomberg Crude Oil [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 54,276 | 172,684
Pro Shares UltraPro 3X Short Crude Oil ETF [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 4,627 | 7,826
ProShares UltraShort Bloomberg Natural Gas [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 1,138 | 1,903
ProShares UltraShort Gold [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 1,537 | 13,526
ProShares Ultra Bloomberg Crude Oil [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 135,612 | 531,483
Proshares Ultra Pro 3X Crude Oil ETF [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 9,352 | 18,464
ProShares Ultra Bloomberg Natural Gas [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 3,499 | 10,369
ProShares Ultra Gold [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | 1,755 | 11,130
ProShares Ultra Silver [Member] |  |
Creation And Redemption Of Creation Units [Line Items] |  |
Transaction fees | $ 6,058 | $ 23,746

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