Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 103,295	$ 172,416
Gross Debt, Long-term Outstanding	1,352,383	1,259,196
Debt issuance costs, Current Outstanding	(3,544)	(2,820)
Debt issuance costs, Long-term Outstanding	(9,107)	(10,139)
Total Debt, Current Outstanding	99,751	169,596
Total Debt, Long-term Outstanding	1,343,276	1,249,057
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	31,056	60,382
Total Debt, Long-term Outstanding	66,347	59,445
Revolving Credit Facility [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		34,500
Gross Debt, Long-term Outstanding	$ 202,500	$ 126,000
Average Interest	2.00%	1.90%
Maturity	Oct. 22, 2020
Revolving Credit Facility [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 4,500	$ 8,500
Gross Debt, Long-term Outstanding	$ 504,000	$ 488,000
Average Interest	2.30%	1.80%
Maturity	Mar. 15, 2020
Loan [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 1,148	$ 1,119
Gross Debt, Long-term Outstanding	$ 18,016	$ 18,881
Average Interest	3.40%	3.40%
Maturity	Dec. 22, 2020
Loan [Member] \| Development Bank of Japan [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 1,800	$ 1,800
Gross Debt, Long-term Outstanding	$ 22,350	$ 23,700
Average Interest	2.60%	2.30%
Maturity	Apr. 30, 2018
Loan [Member] \| Consortium of Banks, Note Dated October 1, 2014 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 9,000	$ 9,000
Gross Debt, Long-term Outstanding	$ 123,000	$ 129,750
Average Interest	2.20%	2.20%
Maturity	Oct. 01, 2019
Loan [Member] \| Consortium of Banks, Note Dated April 11, 2012 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 7,000	$ 9,940
Gross Debt, Long-term Outstanding	$ 91,250	$ 99,440
Average Interest	2.40%	1.90%
Maturity	Jun. 30, 2021
Loan [Member] \| Consortium Of Banks Note Dated August 30 2016 [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	$ 2,681
Total Debt, Long-term Outstanding	$ 47,050
Average Interest	3.60%
Maturity	Aug. 01, 2021
Loan [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 1,829	$ 1,829
Gross Debt, Long-term Outstanding	$ 3,998	$ 5,748
Average Interest	2.70%	2.60%
Maturity	Jun. 01, 2019
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 6,110	$ 7,175
Gross Debt, Long-term Outstanding	$ 64,995	$ 71,105
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
Gross Debt, Long-term Outstanding	$ 212,875	$ 242,875
Average Interest	3.40%	3.40%
Maturity	Mar. 01, 2028
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 29,227	$ 58,553
Gross Debt, Long-term Outstanding	$ 62,349	$ 53,697
Average Interest	1.00%	0.70%
Maturity	Jun. 01, 2019

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Debt Instrument Carrying Amount Noncurrent

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- Definition

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.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Weighted average interest rate of debt outstanding.

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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