Summary Of Significant Accounting Policies (Schedule Of Rental Equipment Useful Lives and Residual Value) (Details)	12 Months Ended
	Dec. 31, 2017 USD ($)
20-ft. Standard Dry Van Container [Member]
Property, Plant and Equipment [Line Items]
Residual Value	$ 1,050
Depreciable Life in Years	13 years
40-ft. Standard Dry Van Container [Member]
Property, Plant and Equipment [Line Items]
Residual Value	$ 1,300
Depreciable Life in Years	13 years
40-ft. High Cube Dry Van Container [Member]
Property, Plant and Equipment [Line Items]
Residual Value	$ 1,400
Depreciable Life in Years	13 years
20-ft. Refrigerated Container [Member]
Property, Plant and Equipment [Line Items]
Residual Value	$ 2,750
Depreciable Life in Years	12 years
40-ft. High Cube Refrigerated Container [Member]
Property, Plant and Equipment [Line Items]
Residual Value	$ 3,500
Depreciable Life in Years	12 years