Investments in Affiliated Companies (Investments and Distributions) (Details 3) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	$ 0.3	$ 6.6	$ 9.0
Payments to Acquire Equity Method Investments	0.0	0.0	14.1
Proceeds from Equity Method Investment, Distribution	0.7	27.6	41.5
Rail North America [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	0.3	0.4	0.6
Payments to Acquire Equity Method Investments	0.0	0.0	0.0
Proceeds from Equity Method Investment, Distribution	0.1	0.0	6.3
Rail International [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	0.0	0.0	3.9
Portfolio Management [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	0.0	6.2	4.5
Payments to Acquire Equity Method Investments	0.0	0.0	14.1
Proceeds from Equity Method Investment, Distribution	$ 0.6	$ 27.6	$ 35.2

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-03(12))
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=SL94080555-108585

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
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-Section 45
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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.

+ References

No definition available.

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