| Document and Entity Information | Dec. 09, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Dec. 9, 2020 |
| Entity Registrant Name | ICHOR HOLDINGS, LTD. |
| Entity Central Index Key | 0001652535 |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | true |
| Entity File Number | 001-37961 |
| Entity Incorporation, State or Country Code | E9 |
| Entity Tax Identification Number | 00-0000000 |
| Entity Address, Address Line One | 3185 Laurelview Ct. |
| Entity Address, City or Town | Fremont |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94538 |
| City Area Code | 510 |
| Local Phone Number | 897-5200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Ordinary Shares, par value $0.0001 |
| Trading Symbol | ICHR |
| Security Exchange Name | NASDAQ |
