Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
REVENUES
Total revenues	$ 191,777	$ 178,123	$ 546,523	$ 545,809
OPERATING EXPENSES
Property operating expenses	73,925	65,419	203,300	195,340
Depreciation and amortization	81,121	79,264	232,192	239,659
General and administrative expenses	5,875	7,676	15,510	22,731
Other expenses, net	3,816	17,492	9,207	23,139
Total operating expenses	164,737	169,851	460,209	480,869
Interest income	13,432	2,492	45,088	8,784
Interest expense	(37,203)	(44,608)	(145,045)	(125,653)
Gain (loss) on derecognition of leased properties and dispositions of real estate, net	7,127	0	94,512	47,295
Mezzanine / Unconsolidated partnerships investment income, net	0	6,870	0	20,553
Income (loss) from continuing operations before income tax (expense) benefit and discontinued operations	10,396	(26,974)	80,869	15,919
Income tax (expense) benefit			(770)	1,678
Income (loss) from continuing operations	10,671	27,393	80,099	17,597
Income from discontinued operations, net of tax	0	2,578	0	9,769
Net income (loss)	10,671	(24,815)	80,099	27,366
Noncontrolling interests:
Net (income) loss attributable to noncontrolling interests in consolidated real estate partnerships	785	154	3,417	(153)
Net income attributable to preferred noncontrolling interests in AIR Operating Partnership	(1,603)	(1,687)	(4,810)	(5,415)
Net (income) loss attributable to common noncontrolling interests in AIR Operating Partnership	(475)	(1,341)	(3,966)	(1,134)
Net (income) loss attributable to noncontrolling interests	(1,293)	(192)	(5,359)	(6,396)
Net income (loss) attributable to AIR/AIR Operating Partnership	9,378	25,007	74,740	20,970
Net income attributable to AIR preferred stockholders	(43)	0	(136)	0
Net income attributable to participating securities	(46)	(39)	(149)	(125)
Net income (loss) attributable to AIR common stockholders	$ 9,289	$ (25,046)	$ 74,455	$ 20,845
Earnings (loss) per common share - basic
Income (loss) from continuing operations attributable to AIR per common share	$ 0.06	$ (0.23)	$ 0.49	$ 0.09
Income (loss) from discontinued operations attributable to AIR per common share		0.02		0.08
Net income (loss) attributable to AIR common stockholders per share - basic	0.06	(0.21)	0.49	0.17
Earnings (loss) per common share - diluted
Income (loss) from continuing operations attributable to AIR per common share	0.06	(0.23)	0.48	0.09
Income (loss) from discontinued operations attributable to AIR per common share		0.02		0.08
Net income (loss) attributable to AIR common stockholders per share - diluted	$ 0.06	$ (0.21)	$ 0.48	$ 0.17
Weighted average common shares/units outstanding - basic	156,646	119,967	153,289	119,957
Weighted average common shares/units outstanding - diluted	157,042	119,967	153,650	120,035
Continuing Operations [Member]
OPERATING EXPENSES
Income tax (expense) benefit	$ 275	$ 419	$ (770)	$ 1,678
Rental And Other Property Revenues [Member]
REVENUES
Total revenues	190,082	178,123	541,533	545,809
Other Revenues [Member]
REVENUES
Total revenues	1,695	0	4,990	0
Apartment Income REIT, L.P. [Member]
REVENUES
Total revenues	191,777	178,123	546,523	545,809
OPERATING EXPENSES
Property operating expenses	73,925	65,419	203,300	195,340
Depreciation and amortization	81,121	79,264	232,192	239,659
General and administrative expenses	5,875	7,676	15,510	22,731
Other expenses, net	3,816	17,492	9,207	23,139
Total operating expenses	164,737	169,851	460,209	480,869
Interest income	13,432	2,492	45,088	8,784
Interest expense	(37,203)	(44,608)	(145,045)	(125,653)
Gain (loss) on derecognition of leased properties and dispositions of real estate, net	7,127	0	94,512	47,295
Mezzanine / Unconsolidated partnerships investment income, net	0	6,870	0	20,553
Income (loss) from continuing operations before income tax (expense) benefit and discontinued operations	10,396	(26,974)	80,869	15,919
Income tax (expense) benefit			(770)	1,678
Income (loss) from continuing operations	10,671	27,393	80,099	17,597
Income from discontinued operations, net of tax	0	2,578	0	9,769
Net income (loss)	10,671	(24,815)	80,099	27,366
Noncontrolling interests:
Net (income) loss attributable to noncontrolling interests in consolidated real estate partnerships	785	154	3,417	(153)
Net income attributable to preferred noncontrolling interests in AIR Operating Partnership	(1,646)	(1,687)	(4,946)	(5,415)
Net income (loss) attributable to AIR/AIR Operating Partnership	11,456	(24,661)	83,516	27,519
Net income attributable to participating securities	(46)	(39)	(149)	(125)
Net income (loss) attributable to AIR common stockholders	$ 9,764	$ 26,387	$ 78,421	$ 21,979
Earnings (loss) per common share - basic
Income (loss) from continuing operations attributable to AIR per common share	$ 0.06	$ (0.23)	$ 0.49	$ 0.09
Income (loss) from discontinued operations attributable to AIR per common share		0.02		0.08
Net income (loss) attributable to AIR common stockholders per share - basic	0.06	(0.21)	0.49	0.17
Earnings (loss) per common share - diluted
Income (loss) from continuing operations attributable to AIR per common share	0.06	(0.23)	0.48	0.09
Income (loss) from discontinued operations attributable to AIR per common share		0.02		0.08
Net income (loss) attributable to AIR common stockholders per share - diluted	$ 0.06	$ (0.21)	$ 0.48	$ 0.17
Weighted average common shares/units outstanding - basic	164,603	126,399	161,336	126,440
Weighted average common shares/units outstanding - diluted	164,999	126,399	161,697	126,547
Apartment Income REIT, L.P. [Member] | Continuing Operations [Member]
OPERATING EXPENSES
Income tax (expense) benefit	$ 275	$ 419	$ (770)	$ 1,678
Apartment Income REIT, L.P. [Member] | Rental And Other Property Revenues [Member]
REVENUES
Total revenues	190,082	178,123	541,533	545,809
Apartment Income REIT, L.P. [Member] | Other Revenues [Member]
REVENUES
Total revenues	$ 1,695	$ 0	$ 4,990	$ 0