v3.21.2

Document and Entity Information	Sep. 21, 2021
Entity Listings [Line Items]
Document Type	8-K
Amendment Flag	false
Document Period End Date	Sep. 21, 2021
Entity Registrant Name	CAI International, Inc.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-33388
Entity Tax Identification Number	94-3109229
Entity Address, Address Line One	Steuart Tower, 1 Market Plaza
Entity Address, Address Line Two	Suite 2400
Entity Address, City or Town	San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94105
City Area Code	415
Local Phone Number	788-0100
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Entity Central Index Key	0001388430
Common Stock [Member]
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	CAI
Security Exchange Name	NYSE
Series A Preferred Stock [Member]
Entity Listings [Line Items]
Title of 12(b) Security	8.50% Series A Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock, par value $0.0001 per share
Trading Symbol	CAI-PA
Security Exchange Name	NYSE
Series B Preferred Stock [Member]
Entity Listings [Line Items]
Title of 12(b) Security	8.50% Series B Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock, par value $0.0001 per share
Trading Symbol	CAI-PB
Security Exchange Name	NYSE

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

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No definition available.

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- Definition

Area code of city

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No definition available.

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- Definition

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

+ References

No definition available.

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- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

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- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

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Data Type:	xbrli:normalizedStringItemType
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- Definition

Address Line 2 such as Street or Suite number

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No definition available.

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Balance Type:	na
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- Definition

Name of the City or Town

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No definition available.

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- Definition

Code for the postal or zip code

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No definition available.

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- Definition

Name of the state or province.

+ References

No definition available.

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation 12B
-Number 240
-Section 12
-Subsection b-2

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- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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-Section 12
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- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

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- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

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Balance Type:	na
Period Type:	duration

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation 12B
-Number 240
-Section 12
-Subsection b-2

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Balance Type:	na
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- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation 12B
-Number 240
-Section 12
-Subsection b-2

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Data Type:	dei:employerIdItemType
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- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:normalizedStringItemType
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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
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-Section 13e
-Subsection 4c

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Data Type:	xbrli:booleanItemType
Balance Type:	na
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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Exchange Act
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- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection d1-1

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Section 14a
-Number 240
-Subsection 12

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Namespace Prefix:	dei_
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Period Type:	duration

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Securities Act
-Number 230
-Section 425

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- Details

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CAI International, Inc. 8-K