v3.21.1

Schedule of Investments - Foreign Currency Forward Contracts (Detail) - 3 months ended Mar. 31, 2021 - Foreign Currency Forward Contracts [Member]		USD ($)	EUR (€)	JPY (¥)
ProShares Ultra Euro [Member] | Euro Contract [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ (226,734)
ProShares Ultra Euro [Member] | Euro Contract [Member] | Contracts to Purchase [Member] | Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Purchase	[1]	$ 2,592,686	€ 2,210,921
Unrealized Appreciation (Depreciation)/Value	[1]	$ (78,549)
ProShares Ultra Euro [Member] | Euro Contract [Member] | Contracts to Purchase [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Purchase	[1]	$ 4,983,274	4,249,502
Unrealized Appreciation (Depreciation)/Value	[1]	(148,185)
ProShares Ultra Euro [Member] | Euro Contract [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ 4,330
ProShares Ultra Euro [Member] | Euro Contract [Member] | Contracts to Sell [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Sell	[1]	$ (323,658)	(276,000)
Unrealized Appreciation (Depreciation)/Value	[1]	4,330
ProShares Ultra Yen [Member] | Yen Contract [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ (192,043)
ProShares Ultra Yen [Member] | Yen Contract [Member] | Contracts to Purchase [Member] | Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Purchase	[1]	$ 3,003,464		¥ 332,532,517
Unrealized Appreciation (Depreciation)/Value	[1]	$ (106,904)
ProShares Ultra Yen [Member] | Yen Contract [Member] | Contracts to Purchase [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Purchase	[1]	$ 2,381,425		263,662,756
Unrealized Appreciation (Depreciation)/Value	[1]	(85,139)
ProShares Ultra Yen [Member] | Yen Contract [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ 3,041
ProShares Ultra Yen [Member] | Yen Contract [Member] | Contracts to Sell [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Sell	[1]	$ (190,668)		(21,110,000)
Unrealized Appreciation (Depreciation)/Value	[1]	3,041
ProShares UltraShort Euro [Member] | Euro Contract [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ (181,875)
ProShares UltraShort Euro [Member] | Euro Contract [Member] | Contracts to Purchase [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Purchase	[1]	$ 14,163,535	12,078,000
Unrealized Appreciation (Depreciation)/Value	[1]	(181,875)
ProShares UltraShort Euro [Member] | Euro Contract [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ 3,436,568
ProShares UltraShort Euro [Member] | Euro Contract [Member] | Contracts to Sell [Member] | Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Sell	[1]	$ (43,859,422)	(37,401,263)
Unrealized Appreciation (Depreciation)/Value	[1]	$ 1,328,784
ProShares UltraShort Euro [Member] | Euro Contract [Member] | Contracts to Sell [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Sell	[1]	$ (80,273,164)	€ (68,453,199)
Unrealized Appreciation (Depreciation)/Value	[1]	2,107,784
ProShares UltraShort Yen [Member] | Yen Contract [Member] | Contracts to Purchase [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ (30,168)
ProShares UltraShort Yen [Member] | Yen Contract [Member] | Contracts to Purchase [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Purchase	[1]	$ 1,511,159		167,310,000
Unrealized Appreciation (Depreciation)/Value	[1]	(30,168)
ProShares UltraShort Yen [Member] | Yen Contract [Member] | Contracts to Sell [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)/Value	[1]	$ 2,366,090
ProShares UltraShort Yen [Member] | Yen Contract [Member] | Contracts to Sell [Member] | Goldman Sachs International [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Sell	[1]	$ (18,146,236)		(2,009,085,165)
Unrealized Appreciation (Depreciation)/Value	[1]	$ 645,891
ProShares UltraShort Yen [Member] | Yen Contract [Member] | Contracts to Sell [Member] | UBS AG [Member]
Schedule of Investments [Line Items]
Settlement Date	[1]	Apr. 09, 2021
Contract to Sell	[1]	$ (53,245,781)		¥ (5,895,178,875)
Unrealized Appreciation (Depreciation)/Value	[1]	$ 1,720,199
[1] The positions and counterparties herein are as of March 31, 2021. The Fund continually evaluates different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 22
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