Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands		6 Months Ended
Apr. 19, 2018	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 163,919	$ 135,869
Gross Debt, Long-term Outstanding		1,691,446	1,578,666
Debt issuance costs, Current Outstanding		(4,320)	(3,820)
Debt issuance costs, Long-term Outstanding		(11,954)	(7,893)
Total Debt, Current Outstanding		159,599	132,049
Total Debt, Long-term Outstanding		1,679,492	1,570,773
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding		5,500
Total Debt, Long-term Outstanding		$ 322,000	$ 528,000
Average Interest		3.80%	3.20%
Maturity		Jun. 01, 2023
Revolving Credit Facility [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding		$ 305,000	$ 272,000
Average Interest		3.60%	3.20%
Maturity		Oct. 22, 2020
Revolving Credit Facility [Member] \| CAI International GmbH [Member]
Debt Instrument [Line Items]
Total Debt, Long-term Outstanding		$ 19,867	$ 14,736
Average Interest		2.00%	2.00%
Maturity		Sep. 01, 2020
Term Loan [Member]
Debt Instrument [Line Items]
Maturity	Apr. 30, 2023
Term Loan [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 1,219	$ 1,198
Gross Debt, Long-term Outstanding		$ 15,909	$ 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		$ 1,800	$ 21,900
Gross Debt, Long-term Outstanding		$ 28,200
Average Interest		4.40%	3.40%
Maturity		Apr. 30, 2023
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		$ 107,250	$ 111,750
Average Interest		3.70%	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		$ 79,000	$ 82,500
Average Interest		3.80%	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		$ 2,856	$ 2,805
Total Debt, Long-term Outstanding		$ 42,119	$ 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		$ 647,711	$ 377,984
Average Interest		3.80%	3.50%
Maturity		Jun. 01, 2042
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 28,408	$ 22,549
Gross Debt, Long-term Outstanding		$ 68,018	$ 69,441
Average Interest		1.20%	1.20%
Maturity		Mar. 01, 2021
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding		$ 30,237	$ 22,549
Total Debt, Long-term Outstanding		68,560	72,727
Variable Interest Entity, Primary Beneficiary [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		1,829
Gross Debt, Long-term Outstanding		$ 542	$ 3,286
Average Interest		3.00%	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)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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