v3.10.0.1

Statements of Financial Condition (Parenthetical)	Dec. 31, 2017 USD ($)
Short-term U.S. government and agency obligations, cost (Note 3)	$ 2,445,970,899
ProShares Short Euro [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	6,996,595
ProShares Short VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	494,962,509
ProShares UltraShort Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	253,669,155
ProShares UltraShort Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	3,999,667
ProShares Ultra Euro [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	6,996,595
ProShares Ultra Gold [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	88,890,367
ProShares Ultra Silver [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	235,605,469
ProShares Ultra VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	287,546,397
ProShares Ultra Yen [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	1,998,216
ProShares UltraShort Australian Dollar [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	11,984,898
ProShares Ultra Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	459,543,053
ProShares Ultra Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	50,963,586
ProShares UltraShort Euro [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	204,788,208
ProShares UltraShort Gold [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	31,979,626
ProShares UltraShort Silver [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	18,352,808
ProShares UltraShort Yen [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	131,844,652
ProShares VIX Mid-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	20,993,328
ProShares VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost (Note 3)	$ 134,855,770

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