Label	Element	Value
Eaton Vance CLO 2014-1R [Member]
Variable Interest Entity Equity Interest Percentage	ev_VariableInterestEntityEquityInterestPercentage	100.00%
Eaton Vance CLO 2018-1 [Member]
Variable Interest Entity, Equity Interest Percentage Sold	ev_VariableInterestEntityEquityInterestPercentageSold	93.00%
Variable Interest Entity, Proceeds From Sale Of Variable Interest Entity Equity Interest	ev_VariableInterestEntityProceedsFromSaleOfVariableInterestEntityEquityInterest	$ 27,300,000
Variable Interest Entity, Loss On Disposal Of Equity Interest In Variable Interest Entity	ev_VariableInterestEntityLossOnDisposalOfEquityInterestInVariableInterestEntity	$ 7,200,000
Eaton Vance CLO 2020-1 [Member]
Variable Interest Entity, Equity Interest Percentage Purchased	ev_VariableInterestEntityEquityInterestPercentagePurchased	100.00%
Variable Interest Entity, Payment To Acquire Variable Interest Entity Equity Interest	ev_VariableInterestEntityPaymentToAcquireVariableInterestEntityEquityInterest	$ 39,500,000
Total assets	us-gaap_Assets	30,000,000.0
Eaton Vance CLO 2020-2 [Member]
Debt Instrument Carrying Amount	us-gaap_DebtInstrumentCarryingAmount	43,600,000
Line of Credit Facility, Maximum Borrowing Capacity	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity	160,000,000.0
Contribution To CLO Entity	ev_ContributionToCloEntity	$ 40,000,000.0
Eaton Vance CLO 2020-2 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument Basis Spread On Variable Rate	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1	1.30%
Eaton Vance CLO 2020-2 [Member] \| Subsequent Event [Member]
Variable Interest Entity, Equity Interest Percentage Purchased	ev_VariableInterestEntityEquityInterestPercentagePurchased	100.00%
Variable Interest Entity, Payment To Acquire Variable Interest Entity Equity Interest	ev_VariableInterestEntityPaymentToAcquireVariableInterestEntityEquityInterest	$ 34,500,000
Contribution To CLO Entity	ev_ContributionToCloEntity	40,000,000.0
Total assets	us-gaap_Assets	$ 400,000,000
Eaton Vance CLO 2020-2 [Member] \| Scenario, Forecast [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument Basis Spread On Variable Rate	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1	2.00%
Eaton Vance CLO 2013-1 [Member]
Variable Interest Entity Equity Interest Percentage	ev_VariableInterestEntityEquityInterestPercentage	100.00%
Consolidated Warehouse CLO Entities [Member]
Gains Losses Attributable to Company, Net, Consolidated Variable Interest Entity	ev_GainsLossesAttributableToCompanyNetConsolidatedVariableInterestEntity	$ 1,800,000
Gains Losses Attributable to Company, Net, Consolidated Variable Interest Entity	ev_GainsLossesAttributableToCompanyNetConsolidatedVariableInterestEntity	3,100,000
Gains Losses Attributable to Company, Net, Consolidated Variable Interest Entity	ev_GainsLossesAttributableToCompanyNetConsolidatedVariableInterestEntity	$ (500,000)

The amount contributed by the Company to a CLO entity during the period.

No definition available.

Name:	ev_ContributionToCloEntity
Namespace Prefix:	ev_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Net gains (losses) attributable to the Company related to consolidate variable interest entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ev_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The percent of equity interest in a collateralized loan obligation entity held by the Company.

+ References

No definition available.

+ Details

Name:	ev_VariableInterestEntityEquityInterestPercentage
Namespace Prefix:	ev_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percent of equity interest the Company purchased in a collateralized loan obligation entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ev_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percent of equity interest in a collateralized loan obligation entity sold by the Company.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The loss recorded in gains and other investment income, net, on the Company's consolidated Statement of Income as a result of the sale of the Company's equity interest in a collateralized loan obligation entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ev_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow to acquire the equity interest in a collateralized loan obligation entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ev_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from the sale of the Company's equity interest in a collateralized loan obligation entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ev_
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Balance Type:	debit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Details

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