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Asset Impairments and Assets Held for Sale (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2015
Assets Held-for-sale, Long Lived, Fair Value Disclosure		$ 3.4	$ 1.3
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property		66.7	79.4	$ 52.5
Asset Impairment Charges		6.6	9.0	8.6
Equity Method Investment, Net Sales Proceeds				2.3
Cardinal Marine [Domain]
Noncontrolling Interest, Ownership Percentage by Parent					50.00%
Rail North America [Member]
Asset Impairment Charges		0.4	0.6	4.6
Rail International [Member]
Asset Impairment Charges		0.0	3.9	0.3
Portfolio Management [Member]
Asset Impairment Charges		6.2	4.5	3.7
Fair Value, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Asset Impairment Charges		$ 0.0		$ 0.0
Fair Value, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Facility Closing [Member] \| Rail International [Member]
Asset Impairment Charges	$ 5.8		$ 3.0