Schedule of Investments - Futures Contracts Sold (Detail)		Dec. 31, 2016 USD ($) Contract		Dec. 31, 2015 USD ($) Contract
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)		$ (10,309,611)	[1]	$ 10,746,415	[2]
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, Expires January 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[1]	8,491
Notional Amount at Value	[1]	$ 128,426,375
Unrealized Appreciation (Depreciation)	[1]	$ (7,027,685)
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, Expires February 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[1]	5,974
Notional Amount at Value	[1]	$ 99,019,050
Unrealized Appreciation (Depreciation)	[1]	(3,281,926)
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, Expires January 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[2]			17,150
Notional Amount at Value	[2]			$ 317,703,750
Unrealized Appreciation (Depreciation)	[2]			$ 10,805,245
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, Expires February 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[2]			17,151
Notional Amount at Value	[2]			$ 323,725,125
Unrealized Appreciation (Depreciation)	[2]			(58,830)
ProShares UltraShort Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)		$ (12,206,881)	[3]	$ 6,412,656	[4]
ProShares UltraShort Bloomberg Crude Oil [Member] | WTI Crude Oil - NYMEX, Expires March 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[5]	1,401
Notional Amount at Value	[5]	$ 76,578,660
Unrealized Appreciation (Depreciation)	[5]	$ (1,426,815)
ProShares UltraShort Bloomberg Crude Oil [Member] | Crude Oil - NYMEX, Expires March 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[6]			2,367
Notional Amount at Value	[6]			$ 90,348,390
Unrealized Appreciation (Depreciation)	[6]			$ 2,464,513
ProShares UltraShort Bloomberg Natural Gas [Member] | Natural Gas - NYMEX, Expires March 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[7]	219
Notional Amount at Value	[7]	$ 8,067,960
Unrealized Appreciation (Depreciation)	[7]	(482,031)
ProShares UltraShort Bloomberg Natural Gas [Member] | Natural Gas - NYMEX, Expires March 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[8]			886
Notional Amount at Value	[8]			$ 20,936,180
Unrealized Appreciation (Depreciation)	[8]			(2,471,164)
ProShares UltraShort Gold [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)		$ 3,033,566	[3]	$ 1,808,942	[4]
ProShares UltraShort Gold [Member] | Gold Futures - COMEX, Expires February 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[9]	2
Notional Amount at Value	[9]	$ 230,340
Unrealized Appreciation (Depreciation)	[9]	18,980
ProShares UltraShort Gold [Member] | Gold Futures - COMEX, Expires February 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[10]			2
Notional Amount at Value	[10]			$ 212,040
Unrealized Appreciation (Depreciation)	[10]			5,220
ProShares UltraShort Silver [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)		$ 1,384,246	[3]	$ 4,778,279	[4]
ProShares UltraShort Silver [Member] | Silver Futures - COMEX, Expires March 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[11]	2
Notional Amount at Value	[11]	$ 159,890
Unrealized Appreciation (Depreciation)	[11]	$ 27,310
ProShares UltraShort Silver [Member] | Silver Futures - COMEX, Expires March 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[12]			2
Notional Amount at Value	[12]			$ 138,030
Unrealized Appreciation (Depreciation)	[12]			$ 5,970
ProShares Short Euro [Member] | Euro Fx Currency Futures - CME, Expires March 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[13]	120
Notional Amount at Value	[13]	$ 15,861,000
Unrealized Appreciation (Depreciation)	[13]	$ 132,900
ProShares Short Euro [Member] | Euro Fx Currency Futures - CME, Expires March 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[14]			129
Notional Amount at Value	[14]			$ 17,553,675
Unrealized Appreciation (Depreciation)	[14]			$ 243,438
ProShares UltraShort Australian Dollar [Member] | Australian Dollar Fx Currency Futures - CME, Expires March 2017 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[15]	462
Notional Amount at Value	[15]	$ 33,273,240
Unrealized Appreciation (Depreciation)	[15]	$ 1,182,340
ProShares UltraShort Australian Dollar [Member] | Australian Dollar Fx Currency Futures - CME, Expires March 2016 [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	[16]			562
Notional Amount at Value	[16]			$ 40,834,920
Unrealized Appreciation (Depreciation)	[16]			$ (420,270)

[1] Cash collateral in the amount of $55,323,984 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[2] Cash collateral in the amount of $123,528,405 was pledged to cover margin requirements for open futures contracts as of December 31, 2015.

[3] The positions and counterparties herein are as of December 31, 2016. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at anytime.

[4] The positions and counterparties herein are as of December 31, 2015. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at anytime.

[5] Cash collateral in the amount of $4,931,520 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[6] Cash collateral in the amount of $10,154,430 was pledged to cover margin requirements for open futures contracts as of December 31, 2015.

[7] Cash collateral in the amount of $710,655 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[8] Cash collateral in the amount of $2,046,660 was pledged to cover margin requirements for open futures contracts as of December 31, 2015.

[9] Cash collateral in the amount of $13,200 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[10] Cash collateral in the amount of $8,250 was pledged to cover margin requirements for open futures contracts as of December 31, 2015.

[11] Cash collateral in the amount of $14,300 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[12] Cash collateral in the amount of $11,440 was pledged to cover margin requirements for open futures contracts as of December 31, 2015.

[13] Cash collateral in the amount of $402,600 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[14] Cash collateral in the amount of $503,745 was pledged to cover margin requirements for open futures contracts as of December 31, 2015

[15] Cash collateral in the amount of $914,760 was pledged to cover margin requirements for open futures contracts as of December 31, 2016.

[16] Cash collateral in the amount of $57,065 was pledged to cover margin requirements for open futures contracts as of December 31, 2015.