Debt (Schedule Of Debt) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 220,495	$ 222,225
Gross Debt, Long-term Outstanding	1,898,267	1,890,778
Debt issuance costs, Current Outstanding	(3,976)	(4,131)
Debt issuance costs, Long-term Outstanding	(9,633)	(10,656)
Total Debt, Current Outstanding	216,519	218,094
Total Debt, Long-term Outstanding	1,888,634	1,880,122
Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Total Debt, Current Outstanding	25,906	26,931
Total Debt, Long-term Outstanding	91,501	100,849
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 682,000	$ 624,000
Average Interest	2.40%	3.30%
Maturity	Jun. 01, 2023
Revolving Credit Facility [Member] \| CAI Rail [Member]
Debt Instrument [Line Items]
Gross Debt, Long-term Outstanding	$ 137,500	$ 137,500
Average Interest	2.40%	3.30%
Maturity	Oct. 01, 2023
Revolving Credit Facility [Member] \| CAI Euro [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 21,122	$ 21,537
Average Interest	2.00%	2.00%
Maturity	Sep. 01, 2020
Term Loan [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 5,311	$ 5,250
Gross Debt, Long-term Outstanding	$ 29,884	$ 31,234
Average Interest	4.20%	4.20%
Maturity	Feb. 01, 2026
Term Loan [Member] \| Term Loan Due April 2023 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 1,800	$ 1,800
Gross Debt, Long-term Outstanding	$ 25,050	$ 25,500
Average Interest	3.90%	3.90%
Maturity	Apr. 01, 2023
Term Loan [Member] \| Term Loan Due June 2021 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 7,000	$ 7,000
Gross Debt, Long-term Outstanding	$ 66,750	$ 68,500
Average Interest	2.70%	3.50%
Maturity	Jun. 01, 2021
Term Loan [Member] \| Term Loan Due December 2020 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 14,967	$ 15,284
Average Interest	3.40%	3.40%
Maturity	Dec. 01, 2020
Term Loan [Member] \| Term Loan Due August 2021 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 3,043	$ 3,016
Gross Debt, Long-term Outstanding	$ 36,864	$ 37,635
Average Interest	3.60%	3.60%
Maturity	Aug. 01, 2021
Term Loan [Member] \| Term Loan Due October 2023 [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 6,000	$ 6,000
Gross Debt, Long-term Outstanding	$ 85,000	$ 86,500
Average Interest	4.60%	4.60%
Maturity	Oct. 01, 2023
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 6,110	$ 6,110
Gross Debt, Long-term Outstanding	$ 43,610	$ 46,665
Average Interest	4.90%	4.90%
Maturity	Sep. 01, 2022
Collateralized Financing Obligations [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 20,595	$ 21,681
Gross Debt, Long-term Outstanding	$ 61,617	$ 69,615
Average Interest	1.60%	1.50%
Maturity	Feb. 01, 2026
Series 2012-1 Asset-Backed Notes [Member] \| Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 17,100	$ 17,100
Gross Debt, Long-term Outstanding	$ 27,075	$ 31,350
Average Interest	3.50%	3.50%
Maturity	Oct. 01, 2027
Series 2013-1 Asset-Backed Notes [Member] \| Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 22,900	$ 22,900
Gross Debt, Long-term Outstanding	$ 45,800	$ 51,525
Average Interest	3.40%	3.40%
Maturity	Mar. 01, 2028
Series 2017-1 Asset-Backed Notes [Member] \| Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 25,307	$ 25,307
Gross Debt, Long-term Outstanding	$ 158,169	$ 164,496
Average Interest	3.70%	3.70%
Maturity	Jun. 01, 2042
Series 2018-1 Asset-Backed Notes [Member] \| Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 34,890	$ 34,890
Gross Debt, Long-term Outstanding	$ 241,323	$ 250,045
Average Interest	4.00%	4.00%
Maturity	Feb. 01, 2043
Series 2018-2 Asset-Backed Notes [Member] \| Asset Backed Notes [Member]
Debt Instrument [Line Items]
Gross Debt, Current Outstanding	$ 34,350	$ 34,350
Gross Debt, Long-term Outstanding	$ 257,625	$ 266,213
Average Interest	4.40%	4.40%
Maturity	Sep. 01, 2043

Debt Instrument Carrying Amount Current

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- Definition

Debt Instrument Carrying Amount Noncurrent

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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/disclosureRef
-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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts 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.

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