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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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Description Of Business And Significant Accounting Policies (Details) - USD ($) $ in Millions			3 Months Ended			12 Months Ended
	Dec. 29, 2020	Aug. 14, 2020	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2020
Logistics [Member]
Business Acquisition [Line Items]
Cash proceeds from sale of business		$ 6.2			$ 6.2
Rail Lease [Member]
Business Acquisition [Line Items]
Cash proceeds from sale of business	$ 228.1			$ 228.1
Total Billings [Member] \| Customer Concentration Risk [Member] \| Largest Customer [Member]
Business Acquisition [Line Items]
Concentration percentage			18.00%
Total Billings [Member] \| Customer Concentration Risk [Member] \| Second Largest [Member]
Business Acquisition [Line Items]
Concentration percentage			10.00%
Series A Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred stock, dividend rate			8.50%			8.50%
Series B Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred stock, dividend rate			8.50%			8.50%