Supplemental Cash Flow and Noncash Investing Transactions (Details Textual) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) railcar	Dec. 31, 2019 USD ($) railcar	Dec. 31, 2018 USD ($)
Noncash or Part Noncash Divestitures [Line Items]
Portfolio proceeds \| $	$ 131.1	$ 250.3	$ 234.4
Number of railcars received \| railcar	732	157

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.

No definition available.

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