Litigation and Environmental Portland (Details) - Environmental Protection Agency [Member] - Portland Harbor Superfund Site, Willamette River, Portland, Oregon [Member] $ in Billions		12 Months Ended
	Jun. 08, 2016	Dec. 31, 2019 Parties Terminals	Jan. 06, 2017 USD ($)
GATX Terminals Corporation (n/k/a KMLT) [Member]
Accrual for Environmental Loss Contingencies, Gross | $			$ 1.1
Estimated Remedy Implementation Period	13 years
Number of Parties Involved In Site Cleanup Allocation Negotiations | Parties		90
Number of Liquid Terminals		2
KMBT [Member]
Number of Liquid Terminals		2