Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 137,100	$ 98,753
Gross Debt, Long-term Outstanding	1,459,163	1,388,495
Debt issuance costs, Current Outstanding	(3,778)	(3,226)
Debt issuance costs, Long-term Outstanding	(8,575)	(7,996)
Total Debt, Current Outstanding	133,322	95,527
Total Debt, Long-term Outstanding	1,450,588	1,380,499
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	23,365	30,980
Total Debt, Long-term Outstanding	71,086	74,887
Revolving Credit Facility [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 254,000	$ 223,500
Average Interest	2.70%	2.40%
Maturity	Oct. 22, 2020
Revolving Credit Facility [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 407,000	$ 526,000
Average Interest	3.00%	2.50%
Maturity	Mar. 15, 2020
Revolving Credit Facility [Member] \| CAI International GmbH [Member]
Debt Instrument [Line Items]
Total Debt, Long-term Outstanding	$ 14,534
Average Interest	2.00%
Maturity	Sep. 01, 2020
Term Loan [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 1,188	$ 1,158
Gross Debt, Long-term Outstanding	$ 16,827	$ 17,723
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	$ 22,350	$ 1,800
Gross Debt, Long-term Outstanding		$ 21,900
Average Interest	3.20%	2.90%
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	$ 114,000	$ 120,750
Average Interest	2.80%	2.30%
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	$ 84,250	$ 89,500
Average Interest	3.00%	2.50%
Maturity	Jun. 30, 2021
Term Loan [Member] \| Consortium Of Banks Note Dated August 30 2016 [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	$ 2,780	$ 2,705
Total Debt, Long-term Outstanding	$ 44,270	$ 46,365
Average Interest	3.60%	3.60%
Maturity	Aug. 01, 2021
Term Loan [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding		$ 2,287
Gross Debt, Long-term Outstanding	$ 3,743	$ 3,541
Average Interest	2.70%	2.50%
Maturity	Jun. 01, 2019
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 6,110	$ 6,110
Gross Debt, Long-term Outstanding	$ 58,885	$ 64,995
Average Interest	4.90%	4.90%
Maturity	Sep. 13, 2022
Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 65,307	$ 40,000
Gross Debt, Long-term Outstanding	$ 394,311	$ 202,875
Average Interest	3.50%	3.40%
Maturity	Jun. 01, 2042
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 23,365	$ 28,693
Gross Debt, Long-term Outstanding	$ 67,343	$ 71,346
Average Interest	1.30%	1.10%
Maturity	Sep. 01, 2020

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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
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-Section S99
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-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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