Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

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Debt (Narrative) (Details) - USD ($) $ in Thousands		9 Months Ended
Debt (Narrative) (Details) - USD ($) $ in Thousands	Jul. 06, 2017	Sep. 30, 2017	Dec. 31, 2016	Jan. 30, 2015
Debt Instrument [Line Items]
Net book value		$ 1,979,012	$ 1,807,010
Restricted cash		12,217	6,192
Railcars [Member]
Debt Instrument [Line Items]
Net book value		397,200
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Net book value		58,075	$ 62,477
Variable Interest Entity, Primary Beneficiary [Member] \| Containers [Member]
Debt Instrument [Line Items]
Net book value		$ 66,100
Revolving Credit Facility [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Oct. 22, 2020
Average interest rate		2.70%	2.40%
Revolving Credit Facility [Member] \| Consortium of Banks [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Mar. 15, 2020
Maximum credit commitment		$ 960,000		$ 775,000
Available borrowing capacity		813,900
Letters of credit outstanding		$ 100
Average interest rate		3.00%	2.50%
Revolving Credit Facility [Member] \| CAI International GmbH [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Sep. 01, 2020
Average interest rate		2.00%
Term Loan [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Dec. 22, 2020
Average interest rate		3.40%	3.40%
Term Loan [Member] \| Development Bank of Japan [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Apr. 30, 2018
Average interest rate		3.20%	2.90%
Term Loan [Member] \| Consortium of Banks, Note Dated October 1, 2014 [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Oct. 01, 2019
Average interest rate		2.80%	2.30%
Term Loan [Member] \| Consortium of Banks, Note Dated April 11, 2012 [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Jun. 30, 2021
Average interest rate		3.00%	2.50%
Term Loan [Member] \| Consortium Of Banks Note Dated August 30 2016 [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Aug. 01, 2021
Average interest rate		3.60%	3.60%
Term Loan [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Jun. 01, 2019
Long-term debt		$ 3,700
Average interest rate		2.70%	2.50%
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Sep. 13, 2022
Average interest rate		4.90%	4.90%
Asset Backed Notes [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Jun. 01, 2042
Average interest rate		3.50%	3.40%
Asset Backed Notes [Member] \| Class A Asset-Backed Notes [Member]
Debt Instrument [Line Items]
Proceeds from asset backed notes	$ 240,900
Average interest rate	3.60%
Asset Backed Notes [Member] \| Class B Asset-Backed Notes [Member]
Debt Instrument [Line Items]
Proceeds from asset backed notes	$ 12,200
Average interest rate	4.60%
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Debt instrument maturity date		Sep. 01, 2020
Long-term debt		$ 90,700
Average interest rate		1.30%	1.10%