Reportable Segments (Narrative) (Details)	9 Months Ended
	Sep. 30, 2019 terminal airport segment facility
Segment Reporting Information [Line Items]
Number of reportable segments | segment	4
Weighted average remaining lease term	18 years 8 months 12 days
Canada- IMTT
Segment Reporting Information [Line Items]
Number of marine terminals	2
Canada- IMTT | Quebec Marine Terminal
Segment Reporting Information [Line Items]
Number of marine terminals	1
Canada- IMTT | Newfoundland Marine Terminal | Partially Owned
Segment Reporting Information [Line Items]
Number of marine terminals	1
IMTT
Segment Reporting Information [Line Items]
Number of marine terminals	17
Weighted average remaining lease term	1 year 10 months 24 days
Atlantic Aviation
Segment Reporting Information [Line Items]
Number of airport locations | airport	70
MIC Hawaii
Segment Reporting Information [Line Items]
Number of solar projects | facility	2
MIC Hawaii | Minimum
Segment Reporting Information [Line Items]
Life of purchase power agreements	20 years