Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Dec. 31, 2020
Entity Registrant Name	THE INVESTMENT COMPANY OF AMERICA
Entity Central Index Key	0000051931
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Feb. 17, 2021
Document Effective Date	Mar. 01, 2021
Prospectus Date	Mar. 01, 2021
INVESTMENT CO OF AMERICA \| Class 529-F-3
Prospectus:
Trading Symbol	FAOOX
INVESTMENT CO OF AMERICA \| Class 529-F-2
Prospectus:
Trading Symbol	FCIAX
INVESTMENT CO OF AMERICA \| Class T
Prospectus:
Trading Symbol	TICAX
INVESTMENT CO OF AMERICA \| Class 529-T
Prospectus:
Trading Symbol	TIACX
INVESTMENT CO OF AMERICA \| Class F-3
Prospectus:
Trading Symbol	FFICX
INVESTMENT CO OF AMERICA \| Class R-5E
Prospectus:
Trading Symbol	RICHX
INVESTMENT CO OF AMERICA \| Class R-2E
Prospectus:
Trading Symbol	RIBEX
INVESTMENT CO OF AMERICA \| Class R-6
Prospectus:
Trading Symbol	RICGX
INVESTMENT CO OF AMERICA \| Class F-2
Prospectus:
Trading Symbol	ICAFX
INVESTMENT CO OF AMERICA \| Class 529-F-1
Prospectus:
Trading Symbol	CICFX
INVESTMENT CO OF AMERICA \| Class 529-E
Prospectus:
Trading Symbol	CICEX
INVESTMENT CO OF AMERICA \| Class 529-C
Prospectus:
Trading Symbol	CICCX
INVESTMENT CO OF AMERICA \| Class 529-A
Prospectus:
Trading Symbol	CICAX
INVESTMENT CO OF AMERICA \| Class F-1
Prospectus:
Trading Symbol	AICFX
INVESTMENT CO OF AMERICA \| Class C
Prospectus:
Trading Symbol	AICCX
INVESTMENT CO OF AMERICA \| Class R-5
Prospectus:
Trading Symbol	RICFX
INVESTMENT CO OF AMERICA \| Class R-4
Prospectus:
Trading Symbol	RICEX
INVESTMENT CO OF AMERICA \| Class R-3
Prospectus:
Trading Symbol	RICCX
INVESTMENT CO OF AMERICA \| Class R-2
Prospectus:
Trading Symbol	RICBX
INVESTMENT CO OF AMERICA \| Class R-1
Prospectus:
Trading Symbol	RICAX
INVESTMENT CO OF AMERICA \| Class A
Prospectus:
Trading Symbol	AIVSX

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- 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.

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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.

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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 containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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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

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

One of: N-1A (Mutual Fund), N-1 (Open-End Separate Account with No Variable Annuities), N-2 (Closed-End Investment Company), N-3 (Separate Account Registered as Open-End Management Investment Company), N-4 (Variable Annuity UIT Separate Account), N-5 (Small Business Investment Company), N-6 (Variable Life UIT Separate Account), S-1 or S-3 (Face Amount Certificate Company), S-6 (UIT, Non-Insurance Product).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-T
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-Section 313

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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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- Definition

Trading symbol of an instrument as listed on an exchange.

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No definition available.

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- Definition

The date of the prospectus.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Form
-Number N-1A
-Chapter A
-Section 1
-Subsection a
-Paragraph 3

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Prospectus Table.

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