Statements of Financial Condition (Parenthetical) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Short-term U.S. government and agency obligations, cost	$ 3,038,837,465	$ 3,313,585,456
ProShares VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	147,990,045	96,075,481
ProShares VIX Mid-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	45,486,489	25,975,462
ProShares Short VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	170,391,741	535,381,199
ProShares Ultra VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	434,676,067	438,333,277
ProShares UltraShort Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost	205,694,828	79,694,797
ProShares UltraShort Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost	2,899,188	8,114,653
ProShares UltraShort Gold [Member]
Short-term U.S. government and agency obligations, cost	60,540,275	72,981,653
ProShares UltraShort Silver [Member]
Short-term U.S. government and agency obligations, cost	21,549,766	50,730,044
ProShares Short Euro [Member]
Short-term U.S. government and agency obligations, cost	13,164,807	15,153,202
ProShares UltraShort Australian Dollar [Member]
Short-term U.S. government and agency obligations, cost	12,909,895	18,409,449
ProShares UltraShort Euro [Member]
Short-term U.S. government and agency obligations, cost	337,373,566	546,177,230
ProShares UltraShort Yen [Member]
Short-term U.S. government and agency obligations, cost	257,103,135	260,014,650
ProShares Ultra Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost	885,046,303	797,652,302
ProShares Ultra Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost	36,183,384	26,806,648
ProShares Ultra Gold [Member]
Short-term U.S. government and agency obligations, cost	95,356,703	71,908,280
ProShares Ultra Silver [Member]
Short-term U.S. government and agency obligations, cost	295,296,440	238,900,176
ProShares Ultra Euro [Member]
Short-term U.S. government and agency obligations, cost	11,891,729	11,605,665
ProShares Ultra Yen [Member]
Short-term U.S. government and agency obligations, cost	$ 5,283,104	$ 5,069,206