v3.8.0.1

Schedule of Investments - Futures Contracts Sold (Detail)	9 Months Ended
	Sep. 30, 2017 USD ($) Contract
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ 94,244,035
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member] | VIX Futures - CBOE, expires October 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	51,224
Notional Amount at Value	$ 598,040,200
Unrealized Appreciation (Depreciation)	$ 86,369,735
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member] | VIX Futures - CBOE, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	34,126
Notional Amount at Value	$ 444,491,150
Unrealized Appreciation (Depreciation)	7,874,300
ProShares UltraShort Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ (13,678,377)	[1]
ProShares UltraShort Bloomberg Crude Oil [Member] | Futures Contracts Sold [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	1,894
Notional Amount at Value	$ 97,862,980
Unrealized Appreciation (Depreciation)	$ (5,367,489)
Pro Shares UltraPro 3X Short Crude Oil ETF [Member] | Futures Contracts Sold [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	916
Notional Amount at Value	$ 47,329,720
Unrealized Appreciation (Depreciation)	$ (2,423,370)
ProShares UltraShort Bloomberg Natural Gas [Member] | Futures Contracts Sold [Member] | Natural Gas - NYMEX, expires November 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	394
Notional Amount at Value	$ 11,847,580
Unrealized Appreciation (Depreciation)	348,521
ProShares UltraShort Gold [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ 2,961,605	[1]
ProShares UltraShort Gold [Member] | Futures Contracts Sold [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)	(9,540)
ProShares UltraShort Silver [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	$ 2,152,433	[1]
ProShares UltraShort Silver [Member] | Futures Contracts Sold [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
ProShares Short Euro [Member] | Futures Contracts Sold [Member] | Euro Fx Currency Futures - CME, expires December 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	55
Notional Amount at Value	$ 8,156,844
Unrealized Appreciation (Depreciation)	$ 106,206
ProShares UltraShort Australian Dollar [Member] | Futures Contracts Sold [Member] | Australian Dollar Fx Currency Futures - CME, expires December 2017 [Member]
Schedule of Investments [Line Items]
Number of Contracts | Contract	232
Notional Amount at Value	$ 18,179,520
Unrealized Appreciation (Depreciation)	$ 379,490
[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 SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

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-Section 50
-Paragraph 1A
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-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

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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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