Document And Entity Information - shares
9 Months Ended
Jun. 30, 2019
Jul. 31, 2019
Document And Entity Information [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Transition Report false  
Document Period End Date Jun. 30, 2019  
Entity File Number 1-10596  
Entity Registrant Name ESCO TECHNOLOGIES INC.  
Entity Incorporation, State or Country Code MO  
Entity Tax Identification Number 43-1554045  
Entity Address, Address Line One 9900A Clayton Road  
Entity Address, City or Town St. Louis  
Entity Address, State or Province MO  
Entity Address, Postal Zip Code 63124-1186  
City Area Code (314)  
Local Phone Number 213-7200  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Title of 12(b) Security Common Stock, par value $0.01 per share  
Entity Common Stock, Shares Outstanding   25,981,313
Entity Central Index Key 0000866706  
Current Fiscal Year End Date --09-30  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Trading Symbol ESE  
Security Exchange Name NYSE