Cover Page - shares	9 Months Ended
	Sep. 30, 2019	Oct. 29, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	001-32384
Entity Registrant Name	MACQUARIE INFRASTRUCTURE CORPORATION
Entity Incorporation, State or Country Code	DE
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
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
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		86,462,375
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001289790
Current Fiscal Year End Date	--12-31