Document and Entity Information	0 Months Ended
Oct. 31, 2012
Risk/Return:
Document Type	485BPOS
Document Period End Date	Oct. 31, 2012
Registrant Name	LORD ABBETT AFFILIATED FUND INC
Central Index Key	0000002691
Amendment Flag	false
Document Creation Date	Feb. 27, 2013
Document Effective Date	Mar. 01, 2013
Prospectus Date	Mar. 01, 2013

If the value is true, then the document as an amendment to previously-filed/accepted document.

No definition available.

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Namespace Prefix:	dei_
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Period Type:	duration

- Definition

The date the document was made available and submitted, in CCYY-MM-DD format. The date of submission, date of acceptance by the recipient, and the document effective date are all potentially different.

+ References

No definition available.

+ Details

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- Definition

The date when a document, upon receipt and acceptance, becomes officially effective, in CCYY-MM-DD format. Usually it is a system-assigned date time value, but it may be declared by the submitter in some cases.

+ References

No definition available.

+ Details

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Data Type:	xbrli:dateItemType
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- Definition

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements this will be the filing date. The format of the date is CCYY-MM-DD.

+ References

No definition available.

+ Details

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- Definition

The type of document being provided (such as 10-K, 10-Q, N-1A, etc). The document type should be limited to the same value as the supporting SEC submission type. The acceptable values are as follows: S-1, S-3, S-4, S-11, F-1, F-3, F-4, F-9, F-10, 6-K, 8-K, 10, 10-K, 10-Q, 20-F, 40-F, N-1A, 485BPOS, NCSR, N-Q, and Other.

+ References

No definition available.

+ Details

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Namespace Prefix:	dei_
Data Type:	us-types:SECReportItemType
Balance Type:	na
Period Type:	duration

- 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 12b

-Subsection 1

+ Details

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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 12b

-Subsection 1

+ Details

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- Definition

The date of the prospectus.

+ References

Reference 1: 1

-Publisher SEC

-Name Form

-Number N-1A

-Chapter A

-Section 1

-Paragraph 3

-Subsection a

+ Details

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- Details

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