Earnings per Share/Unit (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of securities (in shares)	0.2	0.5	0.4
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.3	0.2
Participating securities outstanding (in shares)	0.3	0.2	0.2
Number of shares of common stock required to redeem preferred OP units tendered for redemption, if parent chooses to redeem in shares rather than cash (in shares)	2.3
AIMCO Properties, L.P.
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of securities (in shares)			0.4
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.3	0.2
Participating securities outstanding (in shares)	0.6	0.3	0.2