| Document and Entity Information | Oct. 02, 2019 |
| Document And Entity Information [Line Items] | |
| Current Fiscal Year End Date | --09-28 |
| Amendment Flag | false |
| Entity Central Index Key | 0000887733 |
| Document Type | 8-K |
| Document Period End Date | Oct. 2, 2019 |
| Entity Registrant Name | Central Garden & Pet Company |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-33268 |
| Entity Tax Identification Number | 68-0275553 |
| Entity Address, Address Line One | 1340 Treat Boulevard |
| Entity Address, Address Line Two | Suite 600 |
| Entity Address, City or Town | Walnut Creek |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94597 |
| City Area Code | 925 |
| Local Phone Number | 948-4000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common Stock |
| Trading Symbol | CENT |
| Security Exchange Name | NASDAQ |
| Common Class A [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Class A Common Stock |
| Trading Symbol | CENTA |
| Security Exchange Name | NASDAQ |
