Property, Plant and Equipment (Rail Group Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Components of Railcar assets leased to others
Rail Group assets leased to others, gross	$ 737,862	$ 750,473	$ 740,809
Less: accumulated depreciation	157,263	158,527	143,740
Railcar assets leased to others, net	$ 580,599	$ 591,946	$ 597,069

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

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-Publisher FASB
-Name Accounting Standards Codification
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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
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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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