Debt And Capital Lease Obligations (Details Of Debt) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Current Outstanding	$ 203,199us-gaap_LongTermDebtCurrent	$ 74,080us-gaap_LongTermDebtCurrent
Long-term Outstanding	1,058,754us-gaap_LongTermDebtNoncurrent	1,058,628us-gaap_LongTermDebtNoncurrent
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Outstanding	289,000	235,000
Average Interest (in hundredths)	1.90%	1.90%
Agreement Terminates	Mar. 01, 2018
Revolving Credit Facility [Member] \| CAI Rail Inc [Member]
Debt Instrument [Line Items]
Long-term Outstanding	61,769	54,469
Average Interest (in hundredths)	1.90%	2.40%
Agreement Terminates	Jul. 01, 2019
Term Loan [Member] \| Development Bank of Japan [Member]
Debt Instrument [Line Items]
Current Outstanding	1,800	8,400
Long-term Outstanding	25,500	27,300
Average Interest (in hundredths)	2.20%	2.30%
Agreement Terminates	Apr. 01, 2018
Term Loan [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Current Outstanding	9,000	7,500
Long-term Outstanding	138,750	111,875
Average Interest (in hundredths)	1.80%	2.50%
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	109,380	119,320
Average Interest (in hundredths)	1.90%	2.20%
Agreement Terminates	Apr. 01, 2017
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Current Outstanding	8,240	8,240
Long-term Outstanding	78,280	86,520
Average Interest (in hundredths)	4.90%	4.90%
Agreement Terminates	Sep. 01, 2022
Asset-backed Securities [Member]
Debt Instrument [Line Items]
Current Outstanding	40,000	40,000
Long-term Outstanding	282,875	322,875
Average Interest (in hundredths)	3.40%	3.40%
Agreement Terminates	Mar. 01, 2028
Collateralized Financing Obligation [Member]
Debt Instrument [Line Items]
Current Outstanding	57,390
Long-term Outstanding	65,184	101,269
Average Interest (in hundredths)	0.80%	1.00%
Agreement Terminates	Jun. 01, 2019
Term Loan Held By VIE [Member]
Debt Instrument [Line Items]
Current Outstanding	1,829
Long-term Outstanding	8,016
Average Interest (in hundredths)	2.60%
Agreement Terminates	Jun. 01, 2019
Short Term Line Of Credit [Member]
Debt Instrument [Line Items]
Current Outstanding	$ 75,000
Average Interest (in hundredths)	1.50%
Agreement Terminates	May 01, 2015

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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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