Property, Plant and Equipment (Components of Rail Group Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Components of Railcar assets leased to others
Rail assets leased to others	$ 750,473	$ 723,004
Less: accumulated depreciation	(158,527)	(138,706)
Railcar assets leased to others, net	$ 591,946	$ 584,298

The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
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Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
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Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41457-112716

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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

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- References

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