Partners' Capital - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Oct. 21, 2020	Feb. 03, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Cash dividends on common stock declared			$ 304,992	$ 241,643	$ 238,067
AIMCO PROPERTIES, L.P. [Member]
Related Party Transaction [Line Items]
Redeemable partnership preferred units redeemed for cash during period (in units)			705,000	169,000	10,000
Redeemable partnership preferred units redeemed in exchange for shares during period (in units)			0
Common OP Units redeemed in exchange for cash during period (in units)			64,000	129,000	224,000
Common OP Units redeemed in exchange for shares during period			159,000	127,000	0
Dividends declared per common share/unit (in dollars per share)			$ 0.41	$ 0.39	$ 0.38
AIMCO PROPERTIES, L.P. [Member] | Special Distribution [Member]
Related Party Transaction [Line Items]
Cash dividends on common stock declared	$ 128,700	$ 72,700
Stock dividends on common stock declared (in shares)	35,400,000	4,800,000
Special distribution, cash paid in lieu of fractional shares		$ 400