XML 26 R1.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Document and Entity Information - USD ($)
 12 Months Ended
Dec. 31, 2019
Feb. 06, 2020
Jun. 28, 2019
Cover [Abstract]      
Entity Registrant Name ONTO INNOVATION INC.    
Trading Symbol ONTO    
Entity Central Index Key 0000704532    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Document Type 10-K    
Document Period End Date Dec. 31, 2019    
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   50,282,160  
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 811,997,653
Entity Interactive Data Current Yes    
Title of 12(b) Security Common Stock, $0.001 par value per share    
Security Exchange Name NYSE    
Entity File Number 001-39110    
Entity Incorporation, State or Country Code DE    
Entity Address, Address Line One 16 Jonspin Road    
Entity Address, City or Town Wilmington    
Entity Address, State or Province MA    
City Area Code 978    
Local Phone Number 253-6200    
Entity Address, Postal Zip Code 01887    
Entity Tax Identification Number 94-2276314    
Document Annual Report true    
Document Transition Report false    
Documents Incorporated by Reference

Items 10, 11, 12, 13 and 14 of Part III of this Annual Report on Form 10-K incorporate by reference information from the definitive proxy statement for the registrant’s annual meeting of stockholders scheduled to be held on May 12, 2020.