v3.21.1

Statements of Financial Condition (Parenthetical) - U.S. Government Agencies Short-term Debt Securities [Member] - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Short-term U.S. government and agency obligations, cost	$ 2,026,810,504	$ 1,034,967,523
ProShares Short Euro [Member]
Short-term U.S. government and agency obligations, cost	999,885
ProShares Short VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	91,994,322	69,998,727
ProShares Ultra Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost	689,932,775	219,996,153
ProShares Ultra Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost	33,996,891	29,999,585
ProShares Ultra Euro [Member]
Short-term U.S. government and agency obligations, cost	999,885
ProShares Ultra Gold [Member]
Short-term U.S. government and agency obligations, cost	86,995,913	74,998,283
ProShares Ultra Silver [Member]
Short-term U.S. government and agency obligations, cost	419,957,178	244,987,251
ProShares Ultra VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	376,960,550	244,990,791
ProShares Ultra Yen [Member]
Short-term U.S. government and agency obligations, cost	499,942
ProShares UltraShort Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost	34,996,872
ProShares UltraShort Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost	43,997,035	9,999,612
ProShares UltraShort Euro [Member]
Short-term U.S. government and agency obligations, cost	17,998,447	9,999,612
ProShares UltraShort Gold [Member]
Short-term U.S. government and agency obligations, cost	12,998,786
ProShares UltraShort Silver [Member]
Short-term U.S. government and agency obligations, cost	14,998,873
ProShares UltraShort Yen [Member]
Short-term U.S. government and agency obligations, cost	14,498,781
ProShares VIX Mid-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	31,997,344	44,999,073
ProShares VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	$ 152,987,025	$ 84,998,436

X

- Definition

Cost of the investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

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