Schedule of Investments - Swap Agreements (Detail) - USD ($)		12 Months Ended
		Dec. 31, 2016		Dec. 31, 2015
ProShares UltraShort Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)		$ (12,206,881)	[1]	$ 6,412,656	[2]
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Goldman Sachs International Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[1],[3]	0.25%
Termination Date	[1]	Jan. 10, 2017
Notional Amount at Value	[1],[4]	$ (87,898,388)
Unrealized Appreciation (Depreciation)	[1]	$ (3,061,395)
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Societe Generale S.A. Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[1],[3]	0.25%
Termination Date	[1]	Jan. 10, 2017
Notional Amount at Value	[1],[4]	$ (31,195,025)
Unrealized Appreciation (Depreciation)	[1]	$ (1,050,699)
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with UBS AG Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[1],[3]	0.25%
Termination Date	[1]	Jan. 10, 2017
Notional Amount at Value	[1],[4]	$ (89,698,517)
Unrealized Appreciation (Depreciation)	[1]	$ (3,352,596)
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Citibank N.A. Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[1],[3]	0.18%
Termination Date	[1]	Jan. 10, 2017
Notional Amount at Value	[1],[4]	$ (116,603,958)
Unrealized Appreciation (Depreciation)	[1]	(4,742,191)
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Citibank N.A. Based on Bloomberg Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[2],[5]			0.18%
Termination Date	[2]			Jan. 06, 2016
Notional Amount at Value	[2],[4]			$ (19,234,533)
Unrealized Appreciation (Depreciation)	[2]			$ 1,098,278
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Deutsche Bank AG Based on Bloomberg Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[2],[5]			0.25%
Termination Date	[2]			Jan. 06, 2016
Notional Amount at Value	[2],[4]			$ (29,881,854)
Unrealized Appreciation (Depreciation)	[2]			$ 1,722,894
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Goldman Sachs International Based on Bloomberg Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[2],[5]			0.25%
Termination Date	[2]			Jan. 06, 2016
Notional Amount at Value	[2],[4]			$ (17,799,590)
Unrealized Appreciation (Depreciation)	[2]			$ 1,595,552
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Societe Generale S.A. Based on Bloomberg Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[2],[5]			0.25%
Termination Date	[2]			Jan. 06, 2016
Notional Amount at Value	[2],[4]			$ (8,303,436)
Unrealized Appreciation (Depreciation)	[2]			$ 521,142
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with UBS AG Based on Bloomberg Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[2],[5]			0.25%
Termination Date	[2]			Jan. 06, 2016
Notional Amount at Value	[2],[4]			$ (26,258,293)
Unrealized Appreciation (Depreciation)	[2]			1,474,790
ProShares Ultra Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Unrealized Appreciation (Depreciation)		$ 55,358,571	[6]	$ (72,176,589)	[2]
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Deutsche Bank AG Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)	[2],[5]			25.00%
Termination Date	[2]			Jan. 06, 2016
Notional Amount at Value	[2],[4]			$ 292,553,469
Unrealized Appreciation (Depreciation)	[2]			$ (20,221,872)
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Goldman Sachs International Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)		25.00%	[3],[6]	25.00%	[2],[5]
Termination Date		Jan. 10, 2017	[6]	Jan. 06, 2016	[2]
Notional Amount at Value	[4]	$ 379,451,639	[6]	$ 298,419,036	[2]
Unrealized Appreciation (Depreciation)		$ 14,016,906	[6]	$ (20,806,119)	[2]
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Societe Generale S.A. Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)		25.00%	[3],[6]	25.00%	[2],[5]
Termination Date		Jan. 10, 2017	[6]	Jan. 06, 2016	[2]
Notional Amount at Value	[4]	$ 259,616,766	[6]	$ 100,733,521	[2]
Unrealized Appreciation (Depreciation)		$ 8,661,821	[6]	$ (6,357,459)	[2]
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with UBS AG Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)		25.00%	[3],[6]	25.00%	[2],[5]
Termination Date		Jan. 10, 2017	[6]	Jan. 06, 2016	[2]
Notional Amount at Value	[4]	$ 363,331,028	[6]	$ 294,338,185	[2]
Unrealized Appreciation (Depreciation)		$ 14,252,835	[6]	$ (22,281,150)	[2]
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Citibank N.A. Based on Bloomberg WTI Crude Oil Subindex [Member]
Schedule of Investments [Line Items]
Rate Paid (Received)		18.00%	[3],[6]	18.00%	[2],[5]
Termination Date		Jan. 10, 2017	[6]	Jan. 06, 2016	[2]
Notional Amount at Value	[4]	$ 545,083,669	[6]	$ 158,594,078	[2]
Unrealized Appreciation (Depreciation)		$ 18,427,009	[6]	$ (2,509,989)	[2]

[1] The positions and counterparties herein are as of December 31, 2016. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at anytime.

[2] The positions and counterparties herein are as of December 31, 2015. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at anytime.

[3] Reflects the floating financing rate, as of December 31, 2016, on the notional amount of the swap agreement paid to the counterparty or received from the counterparty, excluding any commissions.

[4] For swap agreements, a positive amount represents "long" exposure to the benchmark index. A negative amount represents "short" exposure to the benchmark index.

[5] Reflects the floating financing rate, as of December 31, 2015, on the notional amount of the swap agreement paid to the counterparty or received from the counterparty, excluding any commissions.

[6] The positions and counterparties herein are as of December 31, 2016. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.