| Document and Entity Information | Dec. 12, 2019 |
| Cover [Abstract] | |
| Current Fiscal Year End Date | --12-29 |
| Amendment Flag | true |
| Entity Central Index Key | 0000868780 |
| Document Type | 8-K/A |
| Document Period End Date | Dec. 12, 2019 |
| Entity Registrant Name | DORMAN PRODUCTS, INC. |
| Entity Incorporation, State or Country Code | PA |
| Entity File Number | 000-18914 |
| Entity Tax Identification Number | 23-2078856 |
| Entity Address, Address Line One | 3400 East Walnut Street |
| Entity Address, City or Town | Colmar |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 18915 |
| City Area Code | 215 |
| Local Phone Number | 997-1800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | DORM |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Description | This Current Report on Form 8-K/A amends the Current Report on Form 8-K filed by Dorman Products, Inc. (the “Company”) on December 16, 2019 (the “Original 8-K”) for the sole purpose of attaching the correct version of the Company’s Amended and Restated Bylaws (the “Bylaws”) filed as Exhibit 3.2 to the Original 8-K. As a result of an administrative error, the incorrect version was previously filed with the Original 8-K. This Current Report on Form 8-K/A does not modify or update the disclosures presented in Item 5.03 of the Original 8-K, which are set forth below for reference. |
