Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 173,245	$ 135,869
Gross Debt, Long-term Outstanding	1,577,510	1,578,666
Debt issuance costs, Current Outstanding	(4,317)	(3,820)
Debt issuance costs, Long-term Outstanding	(10,171)	(7,893)
Total Debt, Current Outstanding	168,928	132,049
Total Debt, Long-term Outstanding	1,567,339	1,570,773
Revolving Credit Facility [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 297,000	$ 272,000
Average Interest	3.50%	3.20%
Maturity	Oct. 22, 2020
Revolving Credit Facility [Member] \| CAI International GmbH [Member]
Debt Instrument [Line Items]
Total Debt, Long-term Outstanding	$ 15,163	$ 14,736
Average Interest	2.00%	2.00%
Maturity	Sep. 01, 2020
Revolving Credit Facility [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 215,000	$ 528,000
Average Interest	3.60%	3.20%
Maturity	Mar. 15, 2020
Term Loan [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 1,209	$ 1,198
Gross Debt, Long-term Outstanding	$ 16,218	$ 16,524
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	$ 21,450	$ 21,900
Average Interest	3.80%	3.40%
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
Gross Debt, Long-term Outstanding	$ 109,500	$ 111,750
Average Interest	3.40%	3.10%
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	$ 7,000
Gross Debt, Long-term Outstanding	$ 80,750	$ 82,500
Average Interest	3.60%	3.30%
Maturity	Jun. 30, 2021
Term Loan [Member] \| Consortium Of Banks Note Dated August 30 2016 [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	$ 2,831	$ 2,805
Total Debt, Long-term Outstanding	$ 42,842	$ 43,560
Average Interest	3.60%	3.60%
Maturity	Aug. 01, 2021
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 6,110	$ 6,110
Gross Debt, Long-term Outstanding	$ 55,830	$ 58,885
Average Interest	4.90%	4.90%
Maturity	Sep. 13, 2022
Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 100,197	$ 65,307
Gross Debt, Long-term Outstanding	$ 672,760	$ 377,984
Average Interest	3.70%	3.50%
Maturity	Jun. 01, 2042
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 25,448	$ 22,549
Gross Debt, Long-term Outstanding	$ 69,619	$ 69,441
Average Interest	1.10%	1.20%
Maturity	Mar. 01, 2021
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	$ 25,448	$ 22,549
Total Debt, Long-term Outstanding	72,447	72,727
Variable Interest Entity, Primary Beneficiary [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 2,828	$ 3,286
Average Interest	2.90%	2.70%
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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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

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-Name Accounting Standards Codification
-Topic 835
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-Section 45
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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