| Cover | Aug. 09, 2021 |
| Document Type | 8-K |
| Document Period End Date | Aug. 9, 2021 |
| Entity Registrant Name | Infrastructure & Energy Alternatives, Inc. |
| Entity File Number | 001-37796 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 47-4787177 |
| Entity Address, Postal Zip Code | 46278 |
| City Area Code | (800) |
| Local Phone Number | 688-3775 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001652362 |
| Document Fiscal Year Focus | 2021 |
| Document Fiscal Period Focus | Q3 |
| Entity Address, Address Line One | 6325 Digital Way |
| Entity Address, Address Line Two | Suite 460 |
| Entity Address, City or Town | Indianapolis |
| Entity Address, State or Province | IN |
| Common Stock | |
| Title of 12(b) Security | Common Stock, $0.0001 par value |
| Trading Symbol | IEA |
| Security Exchange Name | NASDAQ |
| Warrant | |
| Title of 12(b) Security | Warrants for Common Stock |
| Trading Symbol | IEAWW |
| Security Exchange Name | NASDAQ |
