v2.4.1.9

Statements of Changes in Shareholders' Equity (Parenthetical)	3 Months Ended
	Mar. 31, 2015
ProShares Managed Futures Strategy [Member]
Addition, shares	200,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember
Redemption, shares	100,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember
Net addition (redemption), shares	100,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember
ProShares VIX Short-Term Futures ETF [Member]
Addition, shares	4,575,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
Redemption, shares	1,150,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
Net addition (redemption), shares	3,425,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
ProShares VIX Mid-Term Futures ETF [Member]
Addition, shares	200,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
Redemption, shares	75,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
Net addition (redemption), shares	125,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
ProShares Short VIX Short-Term Futures ETF [Member]
Addition, shares	2,150,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Redemption, shares	6,250,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Net addition (redemption), shares	(4,100,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
ProShares Ultra VIX Short-Term Futures ETF [Member]
Addition, shares	48,150,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Redemption, shares	16,500,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Net addition (redemption), shares	31,650,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
ProShares UltraShort Bloomberg Crude Oil [Member]
Addition, shares	4,600,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Redemption, shares	2,500,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Net addition (redemption), shares	2,100,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
ProShares UltraShort Bloomberg Natural Gas [Member]
Addition, shares	150,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Redemption, shares	200,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Net addition (redemption), shares	(50,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
ProShares UltraShort Gold [Member]
Addition, shares	100,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
Redemption, shares	150,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
Net addition (redemption), shares	(50,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
ProShares UltraShort Silver [Member]
Addition, shares	250,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
Redemption, shares	150,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
Net addition (redemption), shares	100,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
ProShares Short Euro [Member]
Addition, shares	100,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember
ProShares UltraShort Australian Dollar [Member]
Addition, shares	50,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember
Redemption, shares	150,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember
Net addition (redemption), shares	(100,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember
ProShares UltraShort Euro [Member]
Addition, shares	5,500,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
Redemption, shares	6,450,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
Net addition (redemption), shares	(950,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
ProShares UltraShort Yen [Member]
Addition, shares	650,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
Redemption, shares	1,650,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
Net addition (redemption), shares	(1,000,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
ProShares Ultra Bloomberg Crude Oil [Member]
Addition, shares	136,250,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
Redemption, shares	33,450,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
Net addition (redemption), shares	102,800,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
ProShares Ultra Bloomberg Natural Gas [Member]
Addition, shares	2,050,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
Redemption, shares	1,250,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
Net addition (redemption), shares	800,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
ProShares Ultra Gold [Member]
Addition, shares	50,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
Redemption, shares	100,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
Net addition (redemption), shares	(50,000)ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
ProShares Ultra Silver [Member]
Addition, shares	700,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
Redemption, shares	450,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
Net addition (redemption), shares	250,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
ProShares Ultra Euro [Member]
Addition, shares	800,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember
ProShares Ultra Yen [Member]
Addition, shares	300,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember
Redemption, shares	50,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember
Net addition (redemption), shares	250,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember
ProShares Trust II [Member]
Addition, shares	206,825,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesTrustIiMember
Redemption, shares	70,625,000us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesTrustIiMember
Net addition (redemption), shares	136,200,000ck0001415311_NetAdditionRedemptionOfSharesShares / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesTrustIiMember

X

- Definition

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+ References

No definition available.

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X

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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X

- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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