v3.10.0.1

Schedule of Investments - Foreign Currency Forward Contracts (Detail)		6 Months Ended
		Jun. 30, 2018 USD ($)	Jun. 30, 2018 EUR (€)	Dec. 31, 2017 USD ($)
Schedule of Investments [Line Items]
Total Unrealized Appreciation		$ 83,731,789		$ 62,238,361
ProShares Ultra Euro [Member]
Schedule of Investments [Line Items]
Total Unrealized Appreciation		(172,054)
ProShares Ultra Euro [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	[1]	$ (169,032)
ProShares Ultra Euro [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (77,986)
ProShares Ultra Euro [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (91,046)
ProShares Ultra Euro [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	[1]	$ (3,022)
ProShares Ultra Euro [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (3,022)
ProShares Ultra Euro [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount | €	[1]		€ 7,275,525
ProShares Ultra Euro [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount | €	[1]		8,350,300
ProShares Ultra Euro [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount | €	[1]		(487,200)
ProShares Ultra Euro [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	8,579,954
ProShares Ultra Euro [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	9,848,965
ProShares Ultra Euro [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(566,306)
ProShares Ultra Yen [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Total Unrealized Depreciation	[1]	$ (24,570)
ProShares Ultra Yen [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (11,895)
ProShares Ultra Yen [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (12,675)
ProShares Ultra Yen [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Total Unrealized Depreciation	[1]	$ 311
ProShares Ultra Yen [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ 10
ProShares Ultra Yen [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ 301
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	324,525,000
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	325,871,400
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(2,934,400)
ProShares Ultra Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(7,607,800)
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	2,944,608
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	2,957,555
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(26,527)
ProShares Ultra Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(69,053)
ProShares UltraShort Euro [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	[1]	$ 102,266
ProShares UltraShort Euro [Member] | Contracts to Purchase [Member] | Euro with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Contract Amount/ Notional Amount	[1]	$ 16,184,300	13,852,100
Unrealized Appreciation (Depreciation)	[1]	$ 2,863
ProShares UltraShort Euro [Member] | Contracts to Purchase [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Contract Amount/ Notional Amount	[1]	$ 38,919,886	33,390,600
Unrealized Appreciation (Depreciation)	[1]	99,403
ProShares UltraShort Euro [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	[1]	$ 3,297,684
ProShares UltraShort Euro [Member] | Contracts to Sell [Member] | Euro with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Contract Amount/ Notional Amount	[1]	$ (190,507,072)	(161,505,525)
Unrealized Appreciation (Depreciation)	[1]	$ 1,776,391
ProShares UltraShort Euro [Member] | Contracts to Sell [Member] | Euro with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Contract Amount/ Notional Amount	[1]	$ (223,733,024)	€ (190,156,800)
Unrealized Appreciation (Depreciation)	[1]	1,521,293
ProShares UltraShort Yen [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	[1]	$ (57,960)
ProShares UltraShort Yen [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (7,876)
ProShares UltraShort Yen [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ (50,084)
ProShares UltraShort Yen [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)	[1]	$ 751,278
ProShares UltraShort Yen [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ 356,039
ProShares UltraShort Yen [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Jul. 13, 2018
Unrealized Appreciation (Depreciation)	[1]	$ 395,239
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	194,370,200
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	1,202,284,300
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(9,819,252,600)
ProShares UltraShort Yen [Member] | Contract Amount in Local Currency for Other than USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(10,284,615,200)
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	1,764,388
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Purchase [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	10,915,053
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	(89,092,026)
ProShares UltraShort Yen [Member] | Contract Amount in US Dollars for USD Values [Member] | Contracts to Sell [Member] | Yen with UBS AG [Member]
Schedule of Investments [Line Items]
Contract Amount/ Notional Amount	[1]	$ (93,336,679)
[1] The positions and counterparties herein are as of June 30, 2018. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
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