Document and Entity Information - USD ($)	12 Months Ended
	Oct. 31, 2020	Apr. 30, 2020
Document and Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Oct. 31, 2020
Entity File Number	1-8100
Entity Registrant Name	EATON VANCE CORP
Entity Incorporation State Country Code	MD
Entity Tax Identification Number	04-2718215
Entity Address Address Line 1	Two International Place
Entity Address City Or Town	Boston
Entity Address State Or Province	MA
Entity Address Postal Zip Code	02110
City Area Code	617
Local Phone Number	482-8260
Security 12b Title	Non-Voting Common Stock, $0.00390625 par value
Trading Symbol	EV
Security Exchange Name	NYSE
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Amendment Flag	false
Current Fiscal Year End Date	--10-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2020
Entity Central Index Key	0000350797
Entity Voluntary Filers	No
Entity Well Known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Public Float		$ 4,030,767,061
Voting Common Stock [Member]
Entity Common Stock Shares Outstanding	464,716
Non-Voting Common Stock [Member]
Entity Common Stock Shares Outstanding	114,196,609