Investments in Affiliated Companies (Investments and Distributions) (Details 3) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	$ 9.0	$ 8.6	$ 38.5
Equity Method Investment, Net Sales Proceeds	0.0	2.3	1.0
Payments to Acquire Equity Method Investments	14.1	36.6	25.0
Proceeds from Equity Method Investment, Distribution	41.5	30.9	36.7
Rail North America [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	0.6	4.6	31.2
Payments to Acquire Equity Method Investments	0.0	0.0	0.0
Proceeds from Equity Method Investment, Distribution	6.3	0.7	1.5
Rail International [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	3.9	0.3	0.6
Portfolio Management [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	4.5	3.7	6.7
Payments to Acquire Equity Method Investments	14.1	36.6	25.0
Proceeds from Equity Method Investment, Distribution	35.2	30.2	35.2
Adler Funding Llc [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	$ 0.0	$ 3.0	$ 0.0

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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