Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 98,753	$ 172,416	[1]
Gross Debt, Long-term Outstanding		1,388,495	1,259,196	[1]
Debt issuance costs, Current Outstanding		(3,226)	(3,167)	[1]
Debt issuance costs, Long-term Outstanding		(7,996)	(8,636)	[1]
Total Debt, Current Outstanding		95,527	169,249	[1]
Total Debt, Long-term Outstanding		1,380,499	1,250,560	[1]
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding		30,980	60,382
Total Debt, Long-term Outstanding		74,887	59,445
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	[1]		8,500
Gross Debt, Long-term Outstanding		$ 526,000	$ 488,000	[1]
Average Interest		2.50%	1.80%
Maturity		Mar. 15, 2020
Revolving Credit Facility [Member] | CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	[1]		$ 34,500
Gross Debt, Long-term Outstanding		$ 223,500	$ 126,000	[1]
Average Interest		2.40%	1.90%
Maturity		Oct. 22, 2020
Revolving Credit Facility [Member] | Consortium of Banks [Member]
Debt Instrument [Line Items]
Maturity		Mar. 15, 2020
Term Loan [Member] | CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 1,158	$ 1,119	[1]
Gross Debt, Long-term Outstanding		$ 17,723	$ 18,881	[1]
Average Interest		3.40%	3.40%
Maturity		Dec. 22, 2020
Term Loan [Member] | Development Bank of Japan [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 1,800	$ 1,800	[1]
Gross Debt, Long-term Outstanding		$ 21,900	$ 23,700	[1]
Average Interest		2.90%	2.30%
Maturity		Apr. 30, 2018
Term Loan [Member] | Consortium of Banks, Note Dated October 1, 2014 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 9,000	$ 9,000	[1]
Gross Debt, Long-term Outstanding		$ 120,750	$ 129,750	[1]
Average Interest		2.30%	2.20%
Maturity		Oct. 01, 2019
Term Loan [Member] | Consortium of Banks, Note Dated April 11, 2012 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 7,000	$ 9,940	[1]
Gross Debt, Long-term Outstanding		$ 89,500	$ 99,440	[1]
Average Interest		2.50%	1.90%
Maturity		Jun. 01, 2021
Term Loan [Member] | Consortium Of Banks Note Dated August 30 2016 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 2,705
Gross Debt, Long-term Outstanding		$ 46,365
Average Interest		3.60%
Maturity		Aug. 01, 2021
Term Loan [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 2,287	$ 1,829	[1]
Gross Debt, Long-term Outstanding		$ 3,541	$ 5,748	[1]
Average Interest		2.50%	2.60%
Maturity		Jun. 01, 2019
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 6,110	$ 7,175	[1]
Gross Debt, Long-term Outstanding		$ 64,995	$ 71,105	[1]
Average Interest		4.90%	4.90%
Maturity		Sep. 13, 2022
Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 40,000	$ 40,000	[1]
Gross Debt, Long-term Outstanding		$ 202,875	$ 242,875	[1]
Average Interest		3.40%	3.40%
Maturity		Mar. 01, 2028
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 28,693	$ 58,553	[1]
Gross Debt, Long-term Outstanding		$ 71,346	$ 53,697	[1]
Average Interest		1.10%	0.70%
Maturity		Jun. 01, 2019

[1] Amounts for the year ended December 31, 2015 have been restated for immaterial corrections of identified errors relating to prepaid loan fees (see Note 2 (b) "Correction of Immaterial Errors").