Concentration of Credit Risk and Major Customers (Schedule of Leasing and Lending Revenues) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating Revenues [Member]
Concentration Risk [Line Items]
Percentage of concentration risk	100.00%	100.00%
Transportation, Rail [Member] | MRXX-Interstate Commodities [Member] | Operating Revenues [Member]
Concentration Risk [Line Items]
Percentage of concentration risk	20.00%	16.00%
Transportation, Rail [Member] | Interstate Commodities [Member] | Operating Revenues [Member]
Concentration Risk [Line Items]
Percentage of concentration risk		15.00%
Transportation [Member] | Equipment Cost [Member]
Concentration Risk [Line Items]
Percentage of concentration risk	38.00%	35.00%
Wholesale [Member] | Equipment Cost [Member]
Concentration Risk [Line Items]
Percentage of concentration risk	42.00%	34.00%
Aviation [Member] | Aircraft Service International [Member] | Operating Revenues [Member]
Concentration Risk [Line Items]
Percentage of concentration risk	16.00%	12.00%
Transportation, Other [Member] | Wal-Mart Transportation, LLC [Member] | Operating Revenues [Member]
Concentration Risk [Line Items]
Percentage of concentration risk		10.00%