| Document and Entity Information Document | Nov. 30, 2021 |
| Cover [Abstract] | |
| Entity Central Index Key | 0001101302 |
| Entity Registrant Name | ENTEGRIS INC |
| Amendment Flag | false |
| Document Type | 8-K |
| Document Period End Date | Nov. 30, 2021 |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-32598 |
| Entity Tax Identification Number | 41-1941551 |
| Entity Address, Address Line One | 129 Concord Road, |
| Entity Address, City or Town | Billerica, |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 01821 |
| City Area Code | (978) |
| Local Phone Number | 436-6500 |
| Title of 12(b) Security | Common stock, $0.01 par value per share |
| Trading Symbol | ENTG |
| Security Exchange Name | NASDAQ |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
