| Cover | Aug. 12, 2022 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Aug. 12, 2022 |
| Entity File Number | 001-33834 |
| Entity Registrant Name | RUBICON TECHNOLOGY, INC. |
| Entity Central Index Key | 0001410172 |
| Entity Tax Identification Number | 36-4419301 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 900 East Green Street |
| Entity Address, City or Town | Bensenville |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60106 |
| City Area Code | 847 |
| Local Phone Number | 295-7000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock Par Value. 001 Per Share [Member] | |
| Title of 12(b) Security | Common Stock, par value $.001 per share |
| Trading Symbol | RBCN |
| Security Exchange Name | NASDAQ |
| Preferred Share Purchase Right [Member] | |
| Title of 12(b) Security | Preferred Share Purchase Right |
