| COVER - USD ($) shares in Millions, $ in Billions | 12 Months Ended | | |
| Dec. 31, 2022 | Mar. 13, 2023 | Jun. 30, 2022 |
| Cover [Abstract] | | | |
| Document Type | 10-K/A | | |
| Document Annual Report | true | | |
| Document Period End Date | Dec. 31, 2022 | | |
| Current Fiscal Year End Date | --12-31 | | |
| Document Transition Report | false | | |
| Entity File Number | 001-39546 | | |
| Entity Registrant Name | PROTERRA INC | | |
| Entity Incorporation, State or Country Code | DE | | |
| Entity Tax Identification Number | 90-2099565 | | |
| Entity Address, Address Line One | 1815 Rollins Road | | |
| Entity Address, City or Town | Burlingame | | |
| Entity Address, State or Province | CA | | |
| Entity Address, Postal Zip Code | 94010 | | |
| City Area Code | 864 | | |
| Local Phone Number | 438-0000 | | |
| Title of 12(b) Security | Common Stock, $0.0001 par value per share | | |
| Trading Symbol | PTRA | | |
| Security Exchange Name | NASDAQ | | |
| Entity Well-known Seasoned Issuer | No | | |
| Entity Voluntary Filers | No | | |
| Entity Current Reporting Status | Yes | | |
| Entity Interactive Data Current | Yes | | |
| Entity Filer Category | Large Accelerated Filer | | |
| Entity Small Business | false | | |
| Entity Emerging Growth Company | false | | |
| ICFR Auditor Attestation Flag | true | | |
| Entity Shell Company | false | | |
| Entity Public Float | | | $ 0.9 |
| Entity Common Stock, Shares Outstanding | | 226.4 | |
| Entity Central Index Key | 0001820630 | | |
| Document Fiscal Year Focus | 2022 | | |
| Document Fiscal Period Focus | FY | | |
| Amendment Flag | true | | |
| Amendment Description | Explanatory NoteOn March 17, 2023, Proterra, Inc (“Proterra,” the “Company,” “we,” “us,” or “our”) filed our Annual Report on Form 10-K, with the Securities and Exchange Commission (the “SEC”) for the fiscal year ended December 31, 2022 (the “Original Form 10-K”). This Amendment No. 1 on Form 10-K (the “Amendment No. 1”) is being filed to include the information required by Part III of Form 10-K which was previously omitted in reliance on General Instruction G(3) to Form 10-K, which permits the information in Part III of Form 10-K to be incorporated into Form 10-K by reference from our definitive proxy statement if such statement is filed no later than 120 days after the end of the fiscal year.We are filing this Amendment No. 1 to include Part III information in our Form 10-K because we will not file a definitive proxy statement containing such information within 120 days after the end of the fiscal year covered by the Original Form 10-K. In addition, this Amendment No. 1 deletes the reference on the cover of the Original Form 10-K to the incorporation by reference of portions of our proxy statement into Part III of the Original Form 10-K, as well as refiles Exhibit 10.36 to the Original Form 10-K correcting a clerical error. Pursuant to Rule 12b-15 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), this Amendment No. 1 also contains certifications pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, which are attached hereto. Because no financial statements have been included in this Amendment No. 1 and this Amendment No. 1 does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation SK, paragraphs 3, 4, and 5 of the certifications have been omitted, as permitted by Question 161.01 of the Compliance and Disclosure Interpretations of the Division of Corporation Finance of the SEC. Except as described above, this Amendment No. 1 does not modify or update any of the disclosures set forth in the Original Form 10-K and does not otherwise reflect any events occurring after the filing of the Original Form 10-Kor modify or update those disclosures that may be affected by subsequent events. Furthermore, this Amendment No.1 does not change any previously reported financial results. Information not affected by this Amendment No.1 remains unchanged and reflects the disclosures made at the time the Original Form 10-K was filed. Accordingly, this Amendment No. 1 should be read in conjunction with the Original Form 10- K and the registrant’s other filings with the SEC. | | |
