| Document and Entity Information | Aug. 03, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Aug. 3, 2021 |
| Entity Registrant Name | Macquarie Infrastructure Corp |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-32384 |
| Entity Tax Identification Number | 43-2052503 |
| Entity Address, Address Line One | 125 West 55th Street |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10019 |
| City Area Code | 212 |
| Local Phone Number | 231-1000 |
| Title of 12(b) Security | Common Stock, par value $0.001 per share |
| Trading Symbol | MIC |
| Security Exchange Name | NYSE |
| Written Communications | true |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001289790 |
| Amendment Flag | false |
