Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Dec. 31, 2019
Registrant Name	INVESTMENT CO OF AMERICA
Entity Central Index Key	0000051931
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Feb. 28, 2020
Document Effective Date	Mar. 01, 2020
Prospectus Date	Mar. 01, 2020
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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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