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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