v3.8.0.1

Schedule of Investments - Futures Contracts Purchased (Detail)	9 Months Ended
	Sep. 30, 2017 USD ($) Contract
ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (18,329,321)
ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires October 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	9,373
Notional Amount at Value	$ 109,429,775
Unrealized Appreciation (Depreciation)	$ (16,948,916)
ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	6,252
Notional Amount at Value	$ 81,432,300
Unrealized Appreciation (Depreciation)	(1,380,405)
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (1,941,640)
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires January 2018 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	582
Notional Amount at Value	$ 8,599,050
Unrealized Appreciation (Depreciation)	$ (697,300)
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires February 2018 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	971
Notional Amount at Value	$ 14,783,475
Unrealized Appreciation (Depreciation)	$ (652,385)
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires March 2018 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	971
Notional Amount at Value	$ 15,341,800
Unrealized Appreciation (Depreciation)	$ (547,765)
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires April 2018 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	388
Notional Amount at Value	$ 6,314,700
Unrealized Appreciation (Depreciation)	(44,190)
ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (101,763,031)
ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires October 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	52,495
Notional Amount at Value	$ 612,879,125
Unrealized Appreciation (Depreciation)	$ (93,982,537)
ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	35,008
Notional Amount at Value	$ 455,979,200
Unrealized Appreciation (Depreciation)	(7,780,494)
ProShares Ultra Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ 40,796,900	[1]
ProShares Ultra Bloomberg Crude Oil [Member] | Futures Contracts Purchased [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	5,855
Notional Amount at Value	$ 302,527,850
Unrealized Appreciation (Depreciation)	$ 13,817,653
ProShares UltraPro 3x Crude Oil ETF [Member] | Futures Contracts Purchased [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	440
Notional Amount at Value	$ 22,734,800
Unrealized Appreciation (Depreciation)	$ 1,272,779
ProShares Ultra Bloomberg Natural Gas [Member] | Futures Contracts Purchased [Member] | Natural Gas - NYMEX, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	3,396
Notional Amount at Value	$ 102,117,720
Unrealized Appreciation (Depreciation)	(971,690)
ProShares Ultra Gold [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (8,453,427)	[1]
ProShares Ultra Gold [Member] | Futures Contracts Purchased [Member] | Gold Futures - COMEX, expires December 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	2
Notional Amount at Value	$ 256,960
Unrealized Appreciation (Depreciation)	9,520
ProShares Ultra Silver [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (28,243,802)	[1]
ProShares Ultra Silver [Member] | Futures Contracts Purchased [Member] | Silver Futures - COMEX, expires December 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	2
Notional Amount at Value	$ 166,760
Unrealized Appreciation (Depreciation)	$ (4,940)
[1] The positions and counterparties herein are as of September 30, 2017. 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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=50485924&loc=SL6090603-123010

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