v3.25.2
Cover Page - shares
6 Months Ended
Jun. 30, 2025
Jul. 29, 2025
Cover [Abstract]    
Amendment Flag false  
Document Type 10-Q  
Document Quarterly Report true  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Document Transition Report false  
Current Fiscal Year End Date --12-31  
Document Period End Date Jun. 30, 2025  
Entity Interactive Data Current Yes  
Entity Current Reporting Status Yes  
Entity Registrant Name MKS INC.  
Entity Central Index Key 0001049502  
Trading Symbol MKSI  
Entity Filer Category Large Accelerated Filer  
Entity Shell Company false  
Entity Emerging Growth Company false  
Entity Small Business false  
Entity Common Stock, Shares Outstanding   67,159,003
Entity File Number 0-23621  
Entity Tax Identification Number 04-2277512  
Entity Address, Address Line One 2 Tech Drive,  
Entity Address, City or Town Andover  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 01810  
Entity Incorporation, State or Country Code MA  
City Area Code 978  
Local Phone Number 645-5500  
Security Exchange Name NASDAQ  
Title of 12(b) Security Common Stock