Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2012
Summary of Significant Accounting Policies [Abstract]
Ownership percentage (in hundredths)	80.00%
Property, Plant and Equipment [Line Items]
Reduction in depreciation expense due to change in residual values and estimated useful lives	$ 9,500,000
Increase in pre tax income due to change in residual values and estimated useful lives	9,500,000
Increase in net income	8,300,000
Increase in diluted earnings per share (in dollars per share)	$ 0.41
Accounts Receivable (Owned Fleet) [Abstract]
Percentage of reserve on receivables overdue one to thirty days (in hundredths)	1.00%
Minimum period for general reserve with specific minimum percentage	1 day
Maximum period for general reserve with specific minimum percentage	30 days
Percentage of reserve on receivables overdue one year (in hundredths)	100.00%
Maximum period for general reserve with specific maximum percentage	1 year
Minimum percentage realization for recognition of income tax position (in hundredths)	50.00%
Minimum lease term	1 year
Maximum lease term	8 years
Contracts - Third Party [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	7 years
Minimum [Member] | Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	1 year
Minimum [Member] | Contracts and Customer Relationships-Owned Equipment [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	5 years
Maximum [Member] | Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	10 years
Maximum [Member] | Contracts and Customer Relationships-Owned Equipment [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	7 years
Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	5 years
20-ft. Standard Dry Van Container [Member] | Current [Member]
Property, Plant and Equipment [Line Items]
Residual Value	1,050,000
Depreciable life (in years)	13 years
20-ft. Standard Dry Van Container [Member] | Prior [Member]
Property, Plant and Equipment [Line Items]
Residual Value	950,000
Depreciable life (in years)	12 years 6 months
40-ft. Standard Dry Van Container [Member] | Current [Member]
Property, Plant and Equipment [Line Items]
Residual Value	1,300,000
Depreciable life (in years)	13 years
40-ft. Standard Dry Van Container [Member] | Prior [Member]
Property, Plant and Equipment [Line Items]
Residual Value	1,150,000
Depreciable life (in years)	12 years 6 months
40-ft. High Cube Dry Van Container [Member] | Current [Member]
Property, Plant and Equipment [Line Items]
Residual Value	1,650,000
Depreciable life (in years)	13 years
40-ft. High Cube Dry Van Container [Member] | Prior [Member]
Property, Plant and Equipment [Line Items]
Residual Value	1,300,000
Depreciable life (in years)	12 years 6 months
20-ft. Refrigerated Container [Member] | Current [Member]
Property, Plant and Equipment [Line Items]
Residual Value	2,750,000
Depreciable life (in years)	12 years
20-ft. Refrigerated Container [Member] | Prior [Member]
Property, Plant and Equipment [Line Items]
Residual Value	2,250,000
Depreciable life (in years)	12 years
40-ft. High Cube Refrigerated Container [Member] | Current [Member]
Property, Plant and Equipment [Line Items]
Residual Value	3,500,000
Depreciable life (in years)	12 years
40-ft. High Cube Refrigerated Container [Member] | Prior [Member]
Property, Plant and Equipment [Line Items]
Residual Value	3,000,000
Depreciable life (in years)	12 years
Other Specialized Containers [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Residual Value	1,000,000
Depreciable life (in years)	12 years 6 months
Other Specialized Containers [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Residual Value	$ 3,500,000
Depreciable life (in years)	15 years
Railcar Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	40 years
Railcar Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	43 years