v2.4.0.8

Significant Accounting Policies - Valuation of Investments (Detail) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013
Significant Accounting Policies [Line Items] |  |
Level III portfolio investments | $ 0 | $ 0
ProShares UltraShort DJ-UBS Commodity [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,589,002 | 3,426,225
ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 281,301,351 | 244,018,950
ProShares UltraShort DJ-UBS Natural Gas [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 61,232,570 | 19,317,013
ProShares UltraShort Gold [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 114,389,278 | 154,635,902
ProShares UltraShort Silver [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 74,936,760 | 112,612,409
ProShares Short Euro [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 6,275,157 | 7,868,825
ProShares UltraShort Australian Dollar [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 18,005,588 | 25,116,112
ProShares UltraShort Euro [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 410,586,544 | 424,098,652
ProShares UltraShort Yen [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 405,582,924 | 587,983,948
ProShares Ultra DJ-UBS Commodity [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,296,768 | 2,831,766
ProShares Ultra DJ-UBS Crude Oil [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 115,123,255 | 140,020,164
ProShares Ultra DJ-UBS Natural Gas [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 16,426,567 | 55,264,472
ProShares Ultra Gold [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 136,312,320 | 134,053,416
ProShares Ultra Silver [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 472,557,491 | 465,361,896
ProShares Ultra Australian Dollar [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,968,877 | 2,598,219
ProShares Ultra Euro [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,328,721 | 2,556,825
ProShares Ultra Yen [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,430,622 | 2,769,247
ProShares VIX Short-Term Futures ETF [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 89,123,845 | 190,983,697
ProShares VIX Mid-Term Futures ETF [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 46,688,561 | 41,143,544
ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 144,151,681 | 85,523,576
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 177,573,312 | 113,675,977
Total Trust [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,582,881,194 | 2,815,860,835
Level I - Quoted Prices [Member] | ProShares UltraShort DJ-UBS Commodity [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,486,733 | 3,453,890
Level I - Quoted Prices [Member] | ProShares UltraShort DJ-UBS Crude Oil [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 288,258,596 | 247,584,623
Level I - Quoted Prices [Member] | ProShares UltraShort DJ-UBS Crude Oil [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (6,264,314) | (1,232,773)
Level I - Quoted Prices [Member] | ProShares UltraShort DJ-UBS Natural Gas [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 56,753,250 | 18,274,713
Level I - Quoted Prices [Member] | ProShares UltraShort DJ-UBS Natural Gas [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 4,479,320 | 1,042,300
Level I - Quoted Prices [Member] | ProShares UltraShort Gold [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 105,840,656 | 148,988,329
Level I - Quoted Prices [Member] | ProShares UltraShort Gold [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 16,860 | 14,520
Level I - Quoted Prices [Member] | ProShares UltraShort Silver [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 67,188,850 | 114,826,066
Level I - Quoted Prices [Member] | ProShares UltraShort Silver [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 5,330 | 14,200
Level I - Quoted Prices [Member] | ProShares Short Euro [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 6,227,257 | 7,902,056
Level I - Quoted Prices [Member] | ProShares Short Euro [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 47,900 | (33,231)
Level I - Quoted Prices [Member] | ProShares UltraShort Australian Dollar [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 19,227,467 | 24,198,507
Level I - Quoted Prices [Member] | ProShares UltraShort Australian Dollar [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (1,221,879) | 917,605
Level I - Quoted Prices [Member] | ProShares UltraShort Euro [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 414,310,854 | 437,847,159
Level I - Quoted Prices [Member] | ProShares UltraShort Yen [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 400,736,540 | 558,597,264
Level I - Quoted Prices [Member] | ProShares Ultra DJ-UBS Commodity [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,410,896 | 2,816,688
Level I - Quoted Prices [Member] | ProShares Ultra DJ-UBS Crude Oil [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 112,053,990 | 137,435,610
Level I - Quoted Prices [Member] | ProShares Ultra DJ-UBS Crude Oil [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,109,314 | 626,661
Level I - Quoted Prices [Member] | ProShares Ultra DJ-UBS Natural Gas [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 18,277,978 | 58,921,011
Level I - Quoted Prices [Member] | ProShares Ultra DJ-UBS Natural Gas [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (1,851,411) | (3,656,539)
Level I - Quoted Prices [Member] | ProShares Ultra Gold [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 148,339,252 | 140,880,950
Level I - Quoted Prices [Member] | ProShares Ultra Gold [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (16,860) | (14,560)
Level I - Quoted Prices [Member] | ProShares Ultra Silver [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 530,701,182 | 467,868,976
Level I - Quoted Prices [Member] | ProShares Ultra Silver [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (5,330) | (14,200)
Level I - Quoted Prices [Member] | ProShares Ultra Australian Dollar [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,775,892 | 2,716,439
Level I - Quoted Prices [Member] | ProShares Ultra Australian Dollar [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 192,985 | (118,220)
Level I - Quoted Prices [Member] | ProShares Ultra Euro [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,307,737 | 2,455,863
Level I - Quoted Prices [Member] | ProShares Ultra Yen [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,471,851 | 2,928,556
Level I - Quoted Prices [Member] | ProShares VIX Short-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 94,150,810 | 207,636,383
Level I - Quoted Prices [Member] | ProShares VIX Short-Term Futures ETF [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (5,026,965) | (16,652,686)
Level I - Quoted Prices [Member] | ProShares VIX Mid-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 48,695,771 | 46,040,233
Level I - Quoted Prices [Member] | ProShares VIX Mid-Term Futures ETF [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (2,007,210) | (4,896,689)
Level I - Quoted Prices [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 173,853,508 | 109,533,487
Level I - Quoted Prices [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (29,701,827) | (24,009,911)
Level I - Quoted Prices [Member] | ProShares Short VIX Short-Term Futures ETF [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 169,490,113 | 105,559,022
Level I - Quoted Prices [Member] | ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 8,083,199 | 8,116,955
Level I - Quoted Prices [Member] | Total Trust [Member] | Short-Term U.S. Government and Agencies [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 2,666,559,183 | 2,846,465,825
Level I - Quoted Prices [Member] | Total Trust [Member] | VIX Futures Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (31,160,888) | (39,896,568)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort DJ-UBS Commodity [Member] | Swap Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 102,269 | (27,665)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort DJ-UBS Crude Oil [Member] | Swap Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (692,931) | (2,332,900)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Gold [Member] | Forward Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 8,531,762 | 5,633,053
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Silver [Member] | Forward Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 7,742,580 | (2,227,857)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Euro [Member] | Foreign Currency Forward Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (3,724,310) | (13,748,507)
Level II - Other Significant Observable Inputs [Member] | ProShares UltraShort Yen [Member] | Foreign Currency Forward Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 4,846,384 | 29,386,684
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra DJ-UBS Commodity [Member] | Swap Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (114,128) | 15,078
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra DJ-UBS Crude Oil [Member] | Swap Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 959,951 | 1,957,893
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Gold [Member] | Forward Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (12,010,072) | (6,812,974)
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Silver [Member] | Forward Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (58,138,361) | (2,492,880)
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Euro [Member] | Foreign Currency Forward Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 20,984 | 100,962
Level II - Other Significant Observable Inputs [Member] | ProShares Ultra Yen [Member] | Foreign Currency Forward Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (41,229) | (159,309)
Level II - Other Significant Observable Inputs [Member] | Total Trust [Member] | Forward Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | (53,874,091) | (5,900,658)
Level II - Other Significant Observable Inputs [Member] | Total Trust [Member] | Foreign Currency Forward Contracts [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | 1,101,829 | 15,579,830
Level II - Other Significant Observable Inputs [Member] | Total Trust [Member] | Swap Agreements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Investments, fair value disclosure | $ 255,161 | $ (387,594)

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- Definition Level three portfolio investments for significant unobservable inputs fair value. + References No definition available. + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 + Details
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