Organization (Details Textual)	12 Months Ended
	Dec. 31, 2020 Property apartment_home shares	Sep. 08, 2020 apartment_home Multi_family_apartment
Organization [Line Items]
Number of apartment communities | Multi_family_apartment		12
Number of apartment homes in apartment communities | apartment_home		4,051
Partially Owned Properties [Member]
Organization [Line Items]
Number of apartment communities | Property	99
Number of apartment homes in apartment communities | apartment_home	26,592
Percentage of average ownership of portfolio	94.00%
AIR Operating Partnership [Member]
Organization [Line Items]
Common operating partnership units and equivalents outstanding | shares	159,155,544
Common operating partnership units and equivalents outstanding | shares	148,861,036
Percentage of the Aimco Operating Partnership's common partnership units and equivalents owned by Aimco	93.50%
Percentage of economic interest	94.90%