| Document and Entity Information | Aug. 05, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Aug. 5, 2020 |
| Entity File Number | 001-08931 |
| Entity Registrant Name | CUBIC CORP /DE/ |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 95-1678055 |
| Entity Address, Address Line One | 9333 Balboa Avenue |
| Entity Address, City or Town | San Diego |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92123 |
| City Area Code | 858 |
| Local Phone Number | 277-6780 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, no par value |
| Trading Symbol | CUB |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000026076 |
| Amendment Flag | false |
