Investments - Gross Amounts Not Offset in Statements of Financial Condition (Detail) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
ProShares UltraShort Euro [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	$ 2,034,015	$ 8,109,067
Financial Instruments for the Benefit of (the Funds) / the Counterparties	(2,034,015)	(8,109,067)
ProShares UltraShort Euro [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	1,865,678	8,053,864
Cash Collateral for the Benefit of (the Funds) / the Counterparties	(1,865,678)	(8,053,864)
ProShares Ultra Bloomberg Crude Oil [Member] \| Citibank N.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	13,855,515	18,427,009
Net Amounts of Assets presented in the Statements of Financial Condition	13,855,515	18,427,009
ProShares Ultra Bloomberg Crude Oil [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	11,965,958	14,016,906
Financial Instruments for the Benefit of (the Funds) / the Counterparties	(11,930,988)	(14,016,906)
Net Amounts of Assets presented in the Statements of Financial Condition	34,970
ProShares Ultra Bloomberg Crude Oil [Member] \| Societe Generale S.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	4,548,744	8,661,821
Financial Instruments for the Benefit of (the Funds) / the Counterparties	(4,548,744)	(8,661,821)
ProShares Ultra Bloomberg Crude Oil [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	10,426,683	14,252,835
Cash Collateral for the Benefit of (the Funds) / the Counterparties	(9,900,000)	(14,252,835)
Net Amounts of Assets presented in the Statements of Financial Condition	526,683
ProShares UltraShort Bloomberg Crude Oil [Member] \| Citibank N.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(6,092,070)	(4,742,191)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	6,092,070	4,742,191
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares UltraShort Bloomberg Crude Oil [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(3,900,635)	(3,061,395)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	3,900,635	3,061,395
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares UltraShort Bloomberg Crude Oil [Member] \| Societe Generale S.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(514,835)	(1,050,699)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	514,835	1,050,699
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares UltraShort Bloomberg Crude Oil [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(3,170,837)	(3,352,596)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	3,170,837	3,352,596
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Gold [Member] \| Citibank N.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(2,994,458)	(1,464,982)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	2,994,458	1,464,982
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Gold [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(2,118,074)	(1,112,916)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	2,118,074	1,112,916
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Gold [Member] \| Societe Generale S.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(1,015,643)	(643,587)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	1,015,643	643,587
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Gold [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(2,325,252)	(1,209,622)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	2,325,252	1,209,622
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Silver [Member] \| Citibank N.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(9,405,158)	(6,946,009)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	9,405,158	6,946,009
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Silver [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(7,478,422)	(5,869,092)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	7,478,422	5,869,092
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Silver [Member] \| Societe Generale S.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(3,531,263)	(2,532,729)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	3,531,263	2,532,729
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Silver [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(7,828,959)	(5,628,359)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	7,828,959	5,628,359
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Yen [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(216,458)	(219,736)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	216,458	219,736
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Yen [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(178,851)	(122,340)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	27,993	122,340
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
Net Amounts of Liabilities presented in the Statements of Financial Condition	(150,858)
ProShares UltraShort Gold [Member] \| Citibank N.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	1,045,390	1,147,811
Net Amounts of Assets presented in the Statements of Financial Condition	1,045,390	1,147,811
ProShares UltraShort Gold [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	835,086	881,454
Financial Instruments for the Benefit of (the Funds) / the Counterparties	(692,611)	(874,948)
Net Amounts of Assets presented in the Statements of Financial Condition	142,475	6,506
ProShares UltraShort Gold [Member] \| Societe Generale S.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	267,146	393,006
Financial Instruments for the Benefit of (the Funds) / the Counterparties	(267,146)	(393,006)
ProShares UltraShort Gold [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	813,983	611,295
Cash Collateral for the Benefit of (the Funds) / the Counterparties	(660,000)	(611,295)
Net Amounts of Assets presented in the Statements of Financial Condition	153,983
ProShares UltraShort Silver [Member] \| Citibank N.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	775,445	610,478
Net Amounts of Assets presented in the Statements of Financial Condition	775,445	610,478
ProShares UltraShort Silver [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	671,956	323,829
Financial Instruments for the Benefit of (the Funds) / the Counterparties		(323,829)
Net Amounts of Assets presented in the Statements of Financial Condition	671,956
ProShares UltraShort Silver [Member] \| Societe Generale S.A. [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	143,987	86,543
Financial Instruments for the Benefit of (the Funds) / the Counterparties		(86,543)
Net Amounts of Assets presented in the Statements of Financial Condition	143,987
ProShares UltraShort Silver [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	561,045	363,396
Cash Collateral for the Benefit of (the Funds) / the Counterparties	(350,000)	(363,396)
Net Amounts of Assets presented in the Statements of Financial Condition	211,045
ProShares UltraShort Yen [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	4,588,344	8,256,779
Financial Instruments for the Benefit of (the Funds) / the Counterparties	(4,588,344)	(7,771,819)
Net Amounts of Assets presented in the Statements of Financial Condition		484,960
ProShares UltraShort Yen [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	4,658,535	8,488,158
Cash Collateral for the Benefit of (the Funds) / the Counterparties	(4,550,000)	(7,980,000)
Net Amounts of Assets presented in the Statements of Financial Condition	108,535	508,158
ProShares Ultra Euro [Member] \| Goldman Sachs International [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(103,093)	(239,256)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	103,093	239,256
Cash Collateral for the Benefit of (the Funds) / the Counterparties	0	0
ProShares Ultra Euro [Member] \| UBS AG [Member]
Derivative [Line Items]
Amounts of Recognized Assets presented in the Statements of Financial Condition	(106,267)	(334,754)
Financial Instruments for the Benefit of (the Funds) / the Counterparties	106,267	334,754
Cash Collateral for the Benefit of (the Funds) / the Counterparties	$ 0	$ 0

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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