Debt And Capital Lease Obligations (Details Of Debt) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Current Outstanding	$ 224,088us-gaap_LongTermDebtCurrent	$ 203,199us-gaap_LongTermDebtCurrent
Long-term Outstanding	1,074,661us-gaap_LongTermDebtNoncurrent	1,058,754us-gaap_LongTermDebtNoncurrent
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Outstanding	327,000	289,000
Average Interest (in hundredths)	1.90%	1.90%
Agreement Terminates	Mar. 01, 2020
Revolving Credit Facility [Member] \| CAI Rail Inc [Member]
Debt Instrument [Line Items]
Long-term Outstanding	74,750	61,769
Average Interest (in hundredths)	1.90%	1.90%
Agreement Terminates	Jul. 01, 2019
Revolving Credit Facility [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Agreement Terminates	Mar. 15, 2020
Term Loan [Member] \| Development Bank of Japan [Member]
Debt Instrument [Line Items]
Current Outstanding	1,800	1,800
Long-term Outstanding	25,050	25,500
Average Interest (in hundredths)	2.30%	2.20%
Agreement Terminates	Apr. 01, 2018
Term Loan [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Current Outstanding	9,000	9,000
Long-term Outstanding	136,500	138,750
Average Interest (in hundredths)	1.90%	1.80%
Agreement Terminates	Oct. 01, 2019
Term Loan [Member] \| Consortium of Banks, Note Dated April 11, 2012 [Member]
Debt Instrument [Line Items]
Current Outstanding	9,940	9,940
Long-term Outstanding	106,895	109,380
Average Interest (in hundredths)	1.90%	1.90%
Agreement Terminates	Apr. 01, 2017
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Current Outstanding	8,240	8,240
Long-term Outstanding	74,160	78,280
Average Interest (in hundredths)	4.90%	4.90%
Agreement Terminates	Sep. 01, 2022
Asset Backed Notes [Member]
Debt Instrument [Line Items]
Current Outstanding	40,000	40,000
Long-term Outstanding	272,875	282,875
Average Interest (in hundredths)	3.40%	3.40%
Agreement Terminates	Mar. 01, 2028
Collateralized Financing Obligation [Member]
Debt Instrument [Line Items]
Current Outstanding	78,279	57,390
Long-term Outstanding	49,872	65,184
Average Interest (in hundredths)	0.80%	0.80%
Agreement Terminates	Jun. 01, 2019
Short Term Line Of Credit [Member]
Debt Instrument [Line Items]
Current Outstanding	75,000	75,000
Average Interest (in hundredths)	1.50%	1.50%
Agreement Terminates	May 01, 2016
Variable Interest Entity, Primary Beneficiary [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Current Outstanding	1,829	1,829
Long-term Outstanding	$ 7,559	$ 8,016
Average Interest (in hundredths)	2.60%	2.60%
Agreement Terminates	Jun. 01, 2019

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ 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 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ 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 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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