v3.10.0.1

Investments - Effect of Derivative Instruments on Statements of Operations (Detail) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | $ (92,109,013) | $ (180,675,672) | $ (1,428,741,022) | $ (487,711,764)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 55,761,957 | 1,042,587 | 40,222,543 | (139,321,461)
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts and/or swap agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts and/or swap agreements [Member] | ProShares Short VIX Short-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 56,008,377 |  | (1,827,517,354) |
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 14,232,558 |  | (39,569,847) |
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts and/or swap agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts and/or swap agreements [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (155,817,104) |  | 260,792,676 |
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 7,071,541 |  | 74,528,029 |
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts and/or swap agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts and/or swap agreements [Member] | ProShares VIX Mid-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 247,018 |  | 3,967,454 |
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (3,080,525) |  | 1,837,040 |
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts and/or swap agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts and/or swap agreements [Member] | ProShares VIX Short-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (23,529,528) |  | 53,747,452 |
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 177,711 |  | 14,188,337 |
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts/Changes in Unrealized Appreciation/Depreciation on Futures Contracts [Member] | ProShares Short VIX Short-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income |  | 182,934,500 |  | 282,827,592
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income |  | (24,640,794) |  | 4,520,180
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts/Changes in Unrealized Appreciation/Depreciation on Futures Contracts [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income |  | (153,988,983) |  | (519,504,171)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income |  | 30,318,423 |  | 1,724,768
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts/Changes in Unrealized Appreciation/Depreciation on Futures Contracts [Member] | ProShares VIX Mid-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income |  | (7,047,733) |  | (15,215,051)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income |  | 2,246,125 |  | (1,018,010)
VIX Futures Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts/Changes in Unrealized Appreciation/Depreciation on Futures Contracts [Member] | ProShares VIX Short-Term Futures ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income |  | (33,527,643) |  | (98,755,500)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income |  | 6,215,600 |  | (641,208)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 39,220,725 | (168,596,998) | 151,738,616 | (169,009,085)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 64,077,371 | 28,760,997 | 25,533,633 | (119,104,310)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 3,945,962 | (4,648,049) | 5,080,774 | (19,025,765)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (2,369,992) | (3,330,323) | (7,344,433) | (2,429,899)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares Ultra Gold [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (5,706,990) | 8,452,341 | 2,948,285 | 17,899,831
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (5,799,159) | (9,844,776) | (10,819,851) | (3,444,419)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares Ultra Silver [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (5,627,237) | (10,939,142) | 7,174,506 | 19,262,746
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (4,043,563) | (41,686,389) | (35,893,615) | (14,404,786)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | Proshares Ultra Pro 3x Crude Oil ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 1,740,951 | (1,832,876) | 3,361,776 | (1,833,835)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 6,901,529 | (272,129) | 8,487,486 | 578,453
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares UltraPro 3X Short Crude Oil ETF [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (6,793,148) | 1,878,109 | (11,469,115) | 1,772,343
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (1,707,316) | 416,232 | (2,454,299) | (245,274)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (27,663,521) | 60,376,204 | (75,759,671) | 59,226,337
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (21,642,290) | (14,895,206) | (6,360,359) | 25,044,628
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (759,484) | 49,239 | (12,513) | 1,907,620
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 171,317 | 881,105 | 1,103,321 | 215,351
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares UltraShort Gold [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 1,572,920 | (3,423,637) | (1,696,955) | (8,294,797)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 1,879,470 | 3,811,095 | 3,785,409 | (399,587)
Commodity Contracts [Member] | Net Realized Gain (Loss) on Futures Contracts, Swap and/or Forward Agreements/Changes in Unrealized Appreciation/Depreciation on Futures Contracts, Swap and/or Forward Agreements [Member] | ProShares UltraShort Silver [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 334,485 | 631,112 | (1,262,356) | (2,226,149)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 475,292 | 3,022,382 | 3,178,568 | 1,139,573
Foreign Exchange Contracts [Member] | Net realized gain (loss) on futures and/or foreign currency forward contracts/changes in unrealized appreciation/depreciation on futures and/or foreign currency forward contracts [Member] | ProShares Short Euro [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 443,811 | (817,763) | 64,225 | (735,506)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 16,282 | (65,818) | 253,501 | (318,481)
Foreign Exchange Contracts [Member] | Net realized gain (loss) on futures and/or foreign currency forward contracts/changes in unrealized appreciation/depreciation on futures and/or foreign currency forward contracts [Member] | ProShares Ultra Euro [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (1,110,032) | 2,035,177 | (309,519) | 1,406,509
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 46,013 | (10,405) | (436,206) | 883,923
Foreign Exchange Contracts [Member] | Net realized gain (loss) on futures and/or foreign currency forward contracts/changes in unrealized appreciation/depreciation on futures and/or foreign currency forward contracts [Member] | ProShares Ultra Yen [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | (299,704) | 424,094 | 22,846 | 342,583
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 22,366 | (590,497) | 10,565 | (793)
Foreign Exchange Contracts [Member] | Net realized gain (loss) on futures and/or foreign currency forward contracts/changes in unrealized appreciation/depreciation on futures and/or foreign currency forward contracts [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 415,369 | 64,976 | (704,621) | (467,251)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | 93,610 | (208,036) | 1,284,990 | (1,640,650)
Foreign Exchange Contracts [Member] | Net realized gain (loss) on futures and/or foreign currency forward contracts/changes in unrealized appreciation/depreciation on futures and/or foreign currency forward contracts [Member] | ProShares UltraShort Euro [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 22,934,693 | (36,508,674) | 4,011,451 | (20,829,055)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | (342,410) | 1,694,586 | 9,744,219 | (22,366,371)
Foreign Exchange Contracts [Member] | Net realized gain (loss) on futures and/or foreign currency forward contracts/changes in unrealized appreciation/depreciation on futures and/or foreign currency forward contracts [Member] | ProShares UltraShort Yen [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Realized Gain (Loss) on Derivatives Recognized in Income | 8,333,424 | (16,189,926) | (2,918,979) | (16,461,160)
Change in Unrealized Appreciation/ Depreciation on Derivatives Recognized in Income | $ (417,848) | $ 19,220,415 | $ (833,945) | $ (7,414,549)

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
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