| Cover Page - USD ($) $ in Millions | 12 Months Ended | ||
| Dec. 31, 2020 | Mar. 29, 2021 | Jun. 30, 2020 | |
| Cover [Abstract] | |||
| Document Type | 10-K/A | ||
| Document Annual Report | true | ||
| Document Period End Date | Dec. 31, 2020 | ||
| Current Fiscal Year End Date | --12-31 | ||
| Document Transition Report | false | ||
| Entity File Number | 001-37480 | ||
| Entity Registrant Name | UNIQUE FABRICATING, INC. | ||
| Entity Central Index Key | 0001617669 | ||
| Amendment Flag | true | ||
| Document Fiscal Year Focus | 2020 | ||
| Document Fiscal Period Focus | FY | ||
| Entity Incorporation, State or Country Code | DE | ||
| Entity Tax Identification Number | 46-1846791 | ||
| Entity Address, Address Line One | 800 Standard Parkway | ||
| Entity Address, City or Town | Auburn Hills | ||
| Entity Address, State or Province | MI | ||
| Entity Address, Postal Zip Code | 48326 | ||
| City Area Code | 248 | ||
| Local Phone Number | 853-2333 | ||
| Title of 12(b) Security | Common Stock, par value $.001 per share | ||
| Trading Symbol | UFAB | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Voluntary Filers | No | ||
| Entity Current Reporting Status | Yes | ||
| Entity Interactive Data Current | Yes | ||
| Entity Small Business | true | ||
| Entity Emerging Growth Company | false | ||
| Entity Filer Category | Non-accelerated Filer | ||
| ICFR Auditor Attestation Flag | false | ||
| Entity Shell Company | false | ||
| Entity Common Stock, Shares Outstanding | 9,779,147 | ||
| Entity Public Float | $ 24.4 | ||
| Security Exchange Name | NYSEAMER | ||
| Amendment Description | On April 15, 2021, Unique Fabricating, Inc. (“Unique,” the “Company,” “we,” “us,” or “our”) filed our Annual Report on Form 10-K for the fiscal year ended December 31, 2020 (the “Original Form 10-K”). The Original Form 10-K omitted Part III, Items 10 (Directors, Executive Officers and Corporate Governance), 11 (Executive Compensation), 12 (Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters), 13 (Certain Relationships and Related Transactions, and Director Independence) and 14 (Principal Accountant Fees and Services) in reliance on General Instruction G(3) to Form 10-K, which provides that such information may be either incorporated by reference from the registrant’s definitive proxy statement or included in an amendment to Form 10-K, in either case filed with the Securities and Exchange Commission (the “SEC”) not later than 120 days after the end of the fiscal year. |
