Apartment Income REIT Corp - Ordinary Shares (AIRC) 10-K 16 Feb 24 2023 FY Annual report Financial data

Cover

Cover - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2023	Feb. 12, 2024	Jun. 30, 2023
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Current Fiscal Year End Date	--12-31
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	1-39686
Entity Registrant Name	APARTMENT INCOME REIT CORP.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	84-1299717
Entity Address, Address Line One	4582 South Ulster Street
Entity Address, Address Line Two	Suite 1700
Entity Address, City or Town	Denver
Entity Address, State or Province	CO
Entity Address, Postal Zip Code	80237
City Area Code	303
Local Phone Number	757-8101
Title of 12(b) Security	Class A Common Stock (Apartment Income REIT Corp.)
Trading Symbol	AIRC
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 5.4
Entity Common Stock, Shares Outstanding		144,917,372
Documents Incorporated by Reference	Portions of the definitive Proxy Statement of Apartment Income REIT Corp. to be filed in connection with the 2024 annual meeting of stockholders are incorporated by reference into Part III of this Annual Report on Form 10-K.
Entity Central Index Key	0001820877
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor Firm ID	34
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	Denver, Colorado
Document Financial Statement Error Correction [Flag]	false
Apartment Income REIT, L.P
Document Information [Line Items]
Current Fiscal Year End Date	--12-31
Document Period End Date	Dec. 31, 2023
Entity File Number	0-24497
Entity Registrant Name	APARTMENT INCOME REIT, L.P.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-1275621
Entity Address, Address Line One	4582 South Ulster Street
Entity Address, Address Line Two	Suite 1700
Entity Address, City or Town	Denver
Entity Address, State or Province	CO
Entity Address, Postal Zip Code	80237
City Area Code	303
Local Phone Number	757-8101
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Central Index Key	0000926660
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor Firm ID	34
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	Denver, Colorado
Document Financial Statement Error Correction [Flag]	false

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2023
Auditor [Line Items]
Auditor Location	Denver, Colorado
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Firm ID	34
Apartment Income REIT, L.P
Auditor [Line Items]
Auditor Location	Denver, Colorado
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Firm ID	34

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Buildings and improvements	$ 6,324,857	$ 6,784,965
Land	1,285,710	1,291,429
Total real estate	7,610,567	8,076,394
Accumulated depreciation	(2,245,589)	(2,449,883)
Net real estate	5,364,978	5,626,511
Cash and cash equivalents	91,401	95,797
Restricted cash	26,090	205,608
Investment in unconsolidated real estate partnerships	336,077	41,860
Goodwill	32,286	32,286
Other assets, net	283,920	549,821
Total assets	6,134,752	6,551,883
LIABILITIES AND EQUITY
Non-recourse property debt, net	2,223,791	1,985,430
Term loans, net	473,701	796,713
Revolving credit facility borrowings	115,000	462,000
Unsecured notes payable, net	397,852	397,486
Total indebtedness	3,210,344	3,641,629
Accrued liabilities and other	296,894	513,805
Total liabilities	3,507,238	4,155,434
Commitments and contingencies
Redeemable preferred units	77,140	77,143
Equity:
Perpetual Preferred Stock	2,000	2,000
Common Stock, $0.01 par value, 1,021,175,000 shares authorized at December 31, 2023 and December 31, 2022, and 144,925,604 and 149,086,548 shares issued/outstanding at December 31, 2023 and December 31, 2022, respectively	1,449	1,491
Additional paid-in capital	3,284,716	3,436,635
Accumulated other comprehensive income	22,392	43,562
Distributions in excess of earnings	(958,661)	(1,327,271)
Total AIR equity	2,351,896	2,156,417
Noncontrolling interests in consolidated real estate partnerships	(85,973)	(78,785)
Common noncontrolling interests in AIR Operating Partnership	284,451	241,674
Total equity	2,550,374	2,319,306
Total liabilities, preferred noncontrolling interests in AIR Operating Partnership, and equity	$ 6,134,752	$ 6,551,883

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (in shares)	1,021,175,000	1,021,175,000
Common stock, shares issued (in shares)	144,925,604	149,086,548
Common stock, shares outstanding (in shares)	144,925,604	149,086,548

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
REVENUES
Total revenues	$ 820,036	$ 773,723	$ 740,853
EXPENSES
Property operating expenses	244,095	231,791	235,832
Property management expenses	31,737	29,473	32,269
Depreciation and amortization	342,593	350,945	319,742
General and administrative expenses	25,494	24,939	18,585
Other expenses, net	25,889	9,073	27,220
Total operating expenses	669,808	646,221	633,648
Interest income	8,314	50,264	58,651
Interest expense	(129,654)	(116,459)	(129,467)
Loss on extinguishment of debt	2,008	23,636	156,707
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	677,740	939,806	594,861
Gain on derivative instruments, net	16,742	0	0
Loss from unconsolidated real estate partnerships	(29,648)	(3,504)	(565)
Income before income tax expense	691,714	973,973	473,978
Income tax expense (benefit)	(2,427)	(3,923)	5,246
Net income	689,287	970,050	479,224
Noncontrolling interests:
Net (income) loss attributable to noncontrolling interests in consolidated real estate partnerships	(5,185)	(458)	3,243
Net income attributable to preferred noncontrolling interests in AIR Operating Partnership	(6,280)	(6,388)	(6,413)
Net income attributable to common noncontrolling interests in AIR Operating Partnership	(42,721)	(58,772)	(28,433)
Net income attributable to noncontrolling interests	(54,186)	(65,618)	(31,603)
Net income attributable to AIR	635,101	904,432	447,621
Net income attributable to AIR preferred stockholders	(172)	(172)	(181)
Net income attributable to participating securities	(485)	(618)	(316)
Net income attributable to AIR common stockholders	$ 634,444	$ 903,642	$ 447,124
Net income attributable to AIR common stockholders per share - basic (in dollars per share)	$ 4.29	$ 5.86	$ 2.90
Net income attributable to AIR common stockholders per share - diluted (in dollars per share)	$ 4.27	$ 5.81	$ 2.89
Weighted average common shares/units outstanding - basic (in shares)	147,899	154,093	154,135
Weighted average common shares/units outstanding - diluted (in shares)	150,220	156,587	154,503
Rental and other property revenues
REVENUES
Total revenues	$ 809,875	$ 764,192	$ 733,483
Other revenues
REVENUES
Total revenues	$ 10,161	$ 9,531	$ 7,370

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 689,287	$ 970,050	$ 479,224
Unrealized gain on derivative instruments, net	2,955	47,049	0
Reclassification of interest rate derivative (gain) loss to net income	(25,823)	273	0
Reclassification of unrealized losses on available for sale debt securities	0	0	(3,251)
Comprehensive income	666,419	1,017,372	475,973
Comprehensive income attributable to noncontrolling interests	(52,488)	(69,378)	(31,391)
Comprehensive income attributable to AIR	$ 613,931	$ 947,994	$ 444,582

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Preferred Stock	Total AIR Equity	Total AIR Equity Preferred Stock	Preferred Stock	Preferred Stock Preferred Stock	Common Stock	Additional  Paid- in Capital	Accumulated Other Comprehensive Income (Loss)	Distributions  in Excess  of Earnings	Noncontrolling Interests in Consolidated Real Estate Partnerships	Common Noncontrolling Interests in AIR Operating Partnership
Beginning balance (in shares) at Dec. 31, 2020					20
Beginning balance (in shares) at Dec. 31, 2020							148,861,036
Beginning balance at Dec. 31, 2020	$ 1,308,093		$ 1,306,851		$ 2,000		$ 1,489	$ 3,432,121	$ 3,039	$ (2,131,798)	$ (61,943)	$ 63,185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock, shares						125	7,825,000
Issuance of stock, value	342,470	$ 129	342,470	$ 129		$ 129	$ 79	342,391
Issuance costs	(486)		(486)					(486)
Issuance of AIR Operating Partnership units	121,557											121,557
Redemption of AIR Operating Partnership units	(17,827)											(17,827)
Conversion of AIR Operating Partnership units (in shares)							170,820
Conversion of AIR Operating Partnership units			8,333				$ 1	8,332				(8,333)
Amortization of share-based compensation cost, (in shares)							33,000
Amortization of share-based compensation cost	7,655		3,771					3,771				3,884
Effect of changes in ownership for consolidated entities	0		(21,312)					(21,312)				21,312
Contributions from noncontrolling interests in consolidated real estate partnerships	7,458										7,458
Change in accumulated other comprehensive income	(3,251)		(3,039)						(3,039)			(212)
Net income (loss)	472,811		447,621							447,621	(3,243)	28,433
Common Stock dividends	(269,385)		(269,385)							(269,385)
Preferred Stock dividends	(179)		(179)							(179)
Distributions to noncontrolling interests	(28,129)										(12,913)	(15,216)
Other, net (in shares)							(108,511)
Other, net	(1,761)		(1,749)				$ 1	(1,712)	0	(38)	(242)	230
Ending balance (in shares) at Dec. 31, 2021					145
Ending balance (in shares) at Dec. 31, 2021							156,998,367
Ending balance at Dec. 31, 2021	1,939,155		1,813,025		$ 2,129		$ 1,570	3,763,105	0	(1,953,779)	(70,883)	197,013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Redemption of AIR Operating Partnership units	(11,174)											(11,174)
Conversion of AIR Operating Partnership units (in shares)							3,116
Conversion of AIR Operating Partnership units			119					119				(119)
Amortization of share-based compensation cost	7,966		4,270					4,270				3,696
Effect of changes in ownership for consolidated entities	0		(7,791)					(7,791)				7,791
Contributions from noncontrolling interests in consolidated real estate partnerships	9,206										9,206
Change in accumulated other comprehensive income	47,322		43,562						43,562			3,760
Net income (loss)	963,662		904,432							904,432	458	58,772
Common Stock dividends	(277,639)		(277,639)							(277,639)
Distributions to noncontrolling interests	(35,444)										(17,623)	(17,821)
Other, net (in shares)					(125)		(105,204)
Other, net	(1,629)		(1,322)		$ (129)		$ 1	(909)	0	(285)	(63)	(244)
Repurchases of Common Stock (in shares)							(8,020,139)
Repurchase of Common Stock, net	(316,710)		(316,710)				$ (80)	(316,630)
Purchase of noncontrolling interests in consolidated real estate partnerships	$ (5,409)		(5,529)					(5,529)			120
Ending balance (in shares) at Dec. 31, 2022					20
Ending balance (in shares) at Dec. 31, 2022	149,086,548						149,086,548
Ending balance at Dec. 31, 2022	$ 2,319,306		2,156,417		$ 2,000		$ 1,491	3,436,635	43,562	(1,327,271)	(78,785)	241,674
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of AIR Operating Partnership units	22,383											22,383
Redemption of AIR Operating Partnership units	(18,507)											(18,507)
Amortization of share-based compensation cost	9,296		4,488					4,488				4,808
Effect of changes in ownership for consolidated entities	1,113		(8,260)					(8,260)			(1,398)	10,771
Contributions from noncontrolling interests in consolidated real estate partnerships	5,691										5,691
Change in accumulated other comprehensive income	(22,868)		(21,170)						(21,170)			(1,698)
Net income (loss)	683,007		635,101							635,101	5,185	42,721
Common Stock dividends	(266,422)		(266,422)							(266,422)
Distributions to noncontrolling interests	(32,080)										(14,376)	(17,704)
Other, net (in shares)							(158,656)
Other, net	(72)		219				$ 1	287	0	(69)	(294)	3
Repurchases of Common Stock (in shares)							(4,319,600)
Repurchase of Common Stock, net	(148,956)		(148,956)				$ (43)	(148,913)
Purchase of noncontrolling interests in consolidated real estate partnerships	$ (1,517)		479					479			(1,996)
Ending balance (in shares) at Dec. 31, 2023					20
Ending balance (in shares) at Dec. 31, 2023	144,925,604						144,925,604
Ending balance at Dec. 31, 2023	$ 2,550,374		$ 2,351,896		$ 2,000		$ 1,449	$ 3,284,716	$ 22,392	$ (958,661)	$ (85,973)	$ 284,451

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 689,287	$ 970,050	$ 479,224
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	342,593	350,945	319,742
Loss on extinguishment of debt	2,008	23,636	156,707
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	(677,740)	(939,806)	(594,861)
Income tax expense (benefit)	2,427	3,923	(5,246)
Share-based compensation expense	8,874	7,463	7,360
Other, net	29,231	3,195	7,230
Net changes in operating assets and operating liabilities:
Accounts receivable and other assets, net	5,338	27,864	(19,646)
Accounts payable, accrued liabilities and other	(31,618)	(26,713)	(17,554)
Total adjustments	(318,887)	(549,493)	(146,268)
Net cash provided by operating activities	370,400	420,557	332,956
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of real estate and deposits related to purchases of real estate	(346,626)	(861,320)	(364,055)
Capital expenditures	(173,662)	(192,404)	(174,499)
Contributions to unconsolidated real estate partnerships	(51,836)	0	0
Distributions from unconsolidated real estate partnerships	207,101	0	0
Proceeds from dispositions of real estate	52,066	1,209,241	915,926
Purchase of corporate assets	(15,862)	(13,940)	(5,171)
Proceeds from repayment of note receivable	0	534,127	0
Proceeds from investments in debt securities	0	0	100,852
Other investing activities, net	15,757	(25,447)	5,229
Net cash (used in) provided by investing activities	(313,062)	650,257	478,282
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from non-recourse property debt	1,005,920	54,156	0
Principal repayments on non-recourse property debt	(119,508)	(449,535)	(1,492,446)
Proceeds from term loans	0	0	1,150,000
Repayment of term loans	(325,000)	(350,000)	(350,000)
Net (repayments of) borrowings on revolving credit facility	(347,000)	159,205	36,756
Payment of debt extinguishment costs	(1,115)	(22,680)	(149,725)
Proceeds from the issuance of unsecured notes payable	0	400,000	0
Proceeds from the issuance of Common Stock	0	0	342,470
Payment of dividends to holders of Common Stock	(266,140)	(277,551)	(269,601)
Repurchases of Common Stock	(124,361)	(316,710)	0
Payment of distributions to common noncontrolling interests	(32,485)	(35,472)	(28,170)
Redemptions of noncontrolling interests in the AIR Operating Partnership	0	(13,394)	(17,905)
Contributions from noncontrolling interests in consolidated real estate partnerships	5,691	9,206	7,458
Other financing activities, net	(37,254)	(19,395)	(20,794)
Net cash used in financing activities	(241,252)	(862,170)	(791,957)
NET (DECREASE) INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	(183,914)	208,644	19,281
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT BEGINNING OF PERIOD	301,405	92,761	73,480
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT END OF PERIOD	117,491	301,405	92,761
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid, net of amounts capitalized	128,431	114,340	130,202
Cash paid for income taxes	5,720	5,528	6,763
Non-cash transactions associated with the acquisition or disposition of real estate:
Non-recourse property debt assumed in connection with the acquisition of real estate	101,215	0	259,248
Issuance of common OP Units in connection with acquisition of real estate	22,383	0	121,557
Proceeds from investment in unconsolidated real estate partnerships for contribution of real estate	270,730	0	0
Other non-cash transactions:
Recognition of right-of-use lease assets	0	80,651	0
Recognition of lease liabilities	0	80,651	0
Accrued capital expenditures (at end of period)	5,287	10,701	9,732
Accrued share repurchases (at end of period)	$ 24,595	$ 0	$ 0

Consolidated Balance Sheets OP

Consolidated Balance Sheets OP - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Buildings and improvements	$ 6,324,857	$ 6,784,965
Land	1,285,710	1,291,429
Total real estate	7,610,567	8,076,394
Accumulated depreciation	(2,245,589)	(2,449,883)
Net real estate	5,364,978	5,626,511
Cash and cash equivalents	91,401	95,797
Restricted cash	26,090	205,608
Investment in unconsolidated real estate partnerships	336,077	41,860
Goodwill	32,286	32,286
Other assets, net	283,920	549,821
Total assets	6,134,752	6,551,883
LIABILITIES AND EQUITY
Non-recourse property debt, net	2,223,791	1,985,430
Term loans, net	473,701	796,713
Revolving credit facility borrowings	115,000	462,000
Unsecured notes payable, net	397,852	397,486
Long term debt	3,210,344	3,641,629
Accrued liabilities and other	296,894	513,805
Total liabilities	3,507,238	4,155,434
Commitments and contingencies
Redeemable preferred units	77,140	77,143
Equity:
Noncontrolling interests in consolidated real estate partnerships	85,973	78,785
Total equity	2,550,374	2,319,306
Total liabilities, preferred noncontrolling interests in AIR Operating Partnership, and equity	6,134,752	6,551,883
Apartment Income REIT, L.P
ASSETS
Buildings and improvements	6,324,857	6,784,965
Land	1,285,710	1,291,429
Total real estate	7,610,567	8,076,394
Accumulated depreciation	(2,245,589)	(2,449,883)
Net real estate	5,364,978	5,626,511
Cash and cash equivalents	91,401	95,797
Restricted cash	26,090	205,608
Investment in unconsolidated real estate partnerships	336,077	41,860
Goodwill	32,286	32,286
Other assets, net	283,920	549,821
Total assets	6,134,752	6,551,883
LIABILITIES AND EQUITY
Non-recourse property debt, net	2,223,791	1,985,430
Term loans, net	473,701	796,713
Revolving credit facility borrowings	115,000	462,000
Unsecured notes payable, net	397,852	397,486
Long term debt	3,210,344	3,641,629
Accrued liabilities and other	296,894	513,805
Total liabilities	3,507,238	4,155,434
Redeemable preferred units	77,140	77,143
Equity:
Preferred units	2,000	2,000
General Partner and Special Limited Partner	2,349,896	2,154,417
Limited Partners	284,451	241,674
Partners’ capital attributable to the AIR Operating Partnership	2,636,347	2,398,091
Noncontrolling interests in consolidated real estate partnerships	(85,973)	(78,785)
Total equity	2,550,374	2,319,306
Total liabilities, preferred noncontrolling interests in AIR Operating Partnership, and equity	$ 6,134,752	$ 6,551,883

Consolidated Statements of Op_2

Consolidated Statements of Operations OP - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
REVENUES
Total revenues	$ 820,036	$ 773,723	$ 740,853
EXPENSES
Property operating expenses	244,095	231,791	235,832
Property management expenses	31,737	29,473	32,269
Depreciation and amortization	342,593	350,945	319,742
General and administrative expenses	25,494	24,939	18,585
Other expenses, net	25,889	9,073	27,220
Total operating expenses	669,808	646,221	633,648
Interest income	8,314	50,264	58,651
Interest expense	(129,654)	(116,459)	(129,467)
Loss on extinguishment of debt	(2,008)	(23,636)	(156,707)
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	677,740	939,806	594,861
Gain on derivative instruments, net	16,742	0	0
Loss from unconsolidated real estate partnerships	(29,648)	(3,504)	(565)
Income before income tax expense	691,714	973,973	473,978
Income tax expense (benefit)	(2,427)	(3,923)	5,246
Net income	689,287	970,050	479,224
Net (income) loss attributable to noncontrolling interests in consolidated real estate partnerships	(5,185)	(458)	3,243
Net income attributable to AIR	635,101	904,432	447,621
Net income attributable to AIR preferred stockholders	(172)	(172)	(181)
Net income attributable to participating securities	(485)	(618)	(316)
Net income attributable to AIR common stockholders	$ 634,444	$ 903,642	$ 447,124
Net income attributable to AIR common stockholders per share - basic (in dollars per share)	$ 4.29	$ 5.86	$ 2.90
Net income attributable to AIR common stockholders per share - diluted (in dollars per share)	$ 4.27	$ 5.81	$ 2.89
Weighted average common shares/units outstanding - basic (in shares)	147,899	154,093	154,135
Weighted average common shares/units outstanding - diluted (in shares)	150,220	156,587	154,503
Rental and other property revenues
REVENUES
Total revenues	$ 809,875	$ 764,192	$ 733,483
Other revenues
REVENUES
Total revenues	10,161	9,531	7,370
Apartment Income REIT, L.P
REVENUES
Total revenues	820,036	773,723	740,853
EXPENSES
Property operating expenses	244,095	231,791	235,832
Property management expenses	31,737	29,473	32,269
Depreciation and amortization	342,593	350,945	319,742
General and administrative expenses	25,494	24,939	18,585
Other expenses, net	25,889	9,073	27,220
Total operating expenses	669,808	646,221	633,648
Interest income	8,314	50,264	58,651
Interest expense	(129,654)	(116,459)	(129,467)
Loss on extinguishment of debt	(2,008)	(23,636)	(156,707)
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	677,740	939,806	594,861
Gain on derivative instruments, net	16,742	0	0
Loss from unconsolidated real estate partnerships	(29,648)	(3,504)	(565)
Income before income tax expense	691,714	973,973	473,978
Income tax expense (benefit)	(2,427)	(3,923)	5,246
Net income	689,287	970,050	479,224
Net (income) loss attributable to noncontrolling interests in consolidated real estate partnerships	(5,185)	(458)	3,243
Net income attributable to AIR	684,102	969,592	482,467
Net income attributable to AIR preferred stockholders	(6,452)	(6,560)	(6,594)
Net income attributable to participating securities	(485)	(618)	(316)
Net income attributable to AIR common stockholders	$ 677,165	$ 962,414	$ 475,557
Net income attributable to AIR common stockholders per share - basic (in dollars per share)	$ 4.29	$ 5.86	$ 2.92
Net income attributable to AIR common stockholders per share - diluted (in dollars per share)	$ 4.27	$ 5.81	$ 2.92
Weighted average common shares/units outstanding - basic (in shares)	157,687	164,141	162,739
Weighted average common shares/units outstanding - diluted (in shares)	160,008	166,635	163,108
Apartment Income REIT, L.P | Rental and other property revenues
REVENUES
Total revenues	$ 809,875	$ 764,192	$ 733,483
Apartment Income REIT, L.P | Other revenues
REVENUES
Total revenues	$ 10,161	$ 9,531	$ 7,370

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income OP - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net income	$ 689,287	$ 970,050	$ 479,224
Unrealized gain on derivative instruments, net	2,955	47,049	0
Reclassification of interest rate derivative (gain) loss to net income	(25,823)	273	0
Reclassification of unrealized losses on available for sale debt securities	0	0	(3,251)
Comprehensive income	666,419	1,017,372	475,973
Comprehensive income attributable to noncontrolling interests	(52,488)	(69,378)	(31,391)
Comprehensive income attributable to AIR	613,931	947,994	444,582
Apartment Income REIT, L.P.
Net income	689,287	970,050	479,224
Unrealized gain on derivative instruments, net	2,955	47,049	0
Reclassification of interest rate derivative (gain) loss to net income	(25,823)	273	0
Reclassification of unrealized losses on available for sale debt securities	0	0	(3,251)
Comprehensive income	666,419	1,017,372	475,973
Comprehensive income attributable to noncontrolling interests	(5,185)	(458)	3,243
Comprehensive income attributable to AIR	$ 661,234	$ 1,016,914	$ 479,216

Consolidated Statements of Part

Consolidated Statements of Partners' Capital - USD ($) $ in Thousands	Total	Apartment Income REIT, L.P	Apartment Income REIT, L.P Preferred Units	Apartment Income REIT, L.P General Partner and Special Limited Partner	Apartment Income REIT, L.P Limited Partners	Apartment Income REIT, L.P Partners' Capital Attributable to the AIR Operating Partnership	Apartment Income REIT, L.P Noncontrolling Interests in Consolidated Real Estate Partnerships
Beginning balance at Dec. 31, 2020		$ 1,308,093	$ 2,000	$ 1,304,851	$ 63,185	$ 1,370,036	$ (61,943)
Increase (Decrease) in Partners' Capital [Roll Forward]
Proceeds from the issuance of Common Stock	$ 342,470	342,470		342,470		342,470
Issuance of stock, value	342,470	129	129			129
Issuance costs		(486)		(486)		(486)
Issuance of common partnership units		121,557			121,557	121,557
Issuance of AIR Operating Partnership units	121,557
Redemption of common partnership units		(17,827)			(17,827)	(17,827)
Conversion of common partnership units		0		8,333	(8,333)
Amortization of share-based compensation cost		7,655		3,771	3,884	7,655
Effect of changes in ownership of consolidated entities	0			(21,312)	21,312
Contributions from noncontrolling interests in consolidated real estate partnerships	7,458	7,458					7,458
Change in accumulated other comprehensive income	(3,251)	(3,251)		(3,039)	(212)	(3,251)
Net income (loss)	472,811	472,811		447,621	28,433	476,054	(3,243)
Distributions to common unitholders		(269,385)		(269,385)		(269,385)	0
Distributions to preferred unitholders		(179)		(179)		(179)
Distributions to noncontrolling interests	(28,129)	(28,129)			(15,216)	(15,216)	(12,913)
Other, net		(1,761)		(1,749)	230	(1,519)	(242)
Ending balance at Dec. 31, 2021		1,939,155	2,129	1,810,896	197,013	2,010,038	(70,883)
Increase (Decrease) in Partners' Capital [Roll Forward]
Proceeds from the issuance of Common Stock	0	0
Redemption of common partnership units		(11,174)			(11,174)	(11,174)
Repurchase of common partnership units		(316,710)		(316,710)		(316,710)
Conversion of common partnership units		0		119	(119)
Amortization of share-based compensation cost		7,966		4,270	3,696	7,966
Effect of changes in ownership of consolidated entities		0		(7,791)	7,791
Purchase of noncontrolling interests in consolidated real estate partnerships		(5,409)		(5,529)		(5,529)	120
Contributions from noncontrolling interests in consolidated real estate partnerships	9,206	9,206					9,206
Change in accumulated other comprehensive income	47,322	47,322		43,562	3,760	47,322
Net income (loss)	963,662	963,662		904,432	58,772	963,204	458
Distributions to common unitholders		(295,460)		(277,639)	(17,821)	(295,460)
Distributions to noncontrolling interests	(35,444)	(17,623)					(17,623)
Other, net		(1,629)	(129)	(1,193)	(244)	(1,566)	(63)
Ending balance at Dec. 31, 2022	2,319,306		2,000	2,154,417	241,674	2,398,091	(78,785)
Increase (Decrease) in Partners' Capital [Roll Forward]
Proceeds from the issuance of Common Stock	0	0
Issuance of AIR Operating Partnership units	22,383	22,383			22,383	22,383
Redemption of common partnership units		(18,507)			(18,507)	(18,507)
Repurchase of common partnership units		(148,956)		(148,956)		(148,956)
Amortization of share-based compensation cost		9,296		4,488	4,808	9,296
Effect of changes in ownership of consolidated entities	1,113			(8,260)	10,771	2,511	(1,398)
Purchase of noncontrolling interests in consolidated real estate partnerships		(1,517)		479		479	(1,996)
Contributions from noncontrolling interests in consolidated real estate partnerships	5,691	5,691					5,691
Change in accumulated other comprehensive income	(22,868)	(22,868)		(21,170)	(1,698)	(22,868)
Net income (loss)	683,007	683,007		635,101	42,721	677,822	5,185
Distributions to common unitholders		(284,126)		(266,422)	(17,704)	(284,126)
Distributions to noncontrolling interests	(32,080)	(14,376)					(14,376)
Other, net		$ (72)		219	3	222	(294)
Ending balance at Dec. 31, 2023	$ 2,550,374		$ 2,000	$ 2,349,896	$ 284,451	$ 2,636,347	$ (85,973)

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows OP - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 689,287	$ 970,050	$ 479,224
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	342,593	350,945	319,742
Loss on extinguishment of debt	(2,008)	(23,636)	(156,707)
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	(677,740)	(939,806)	(594,861)
Income tax expense (benefit)	2,427	3,923	(5,246)
Share-based compensation expense	8,874	7,463	7,360
Other, net	29,231	3,195	7,230
Net changes in operating assets and operating liabilities:
Accounts receivable and other assets, net	5,338	27,864	(19,646)
Accounts payable, accrued liabilities and other	(31,618)	(26,713)	(17,554)
Total adjustments	(318,887)	(549,493)	(146,268)
Net cash provided by operating activities	370,400	420,557	332,956
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of real estate and deposits related to purchases of real estate	(346,626)	(861,320)	(364,055)
Capital expenditures	(173,662)	(192,404)	(174,499)
Contributions to unconsolidated real estate partnerships	(51,836)	0	0
Distributions from unconsolidated real estate partnerships	207,101	0	0
Proceeds from dispositions of real estate	52,066	1,209,241	915,926
Purchase of corporate assets	(15,862)	(13,940)	(5,171)
Proceeds from repayment of note receivable	0	534,127	0
Proceeds from investments in debt securities	0	0	100,852
Other investing activities, net	15,757	(25,447)	5,229
Net cash (used in) provided by investing activities	(313,062)	650,257	478,282
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from non-recourse property debt	1,005,920	54,156	0
Principal repayments on non-recourse property debt	(119,508)	(449,535)	(1,492,446)
Proceeds from term loans	0	0	1,150,000
Repayment of term loans	(325,000)	(350,000)	(350,000)
Net (repayments of) borrowings on revolving credit facility	(347,000)	159,205	36,756
Payment of debt extinguishment costs	(1,115)	(22,680)	(149,725)
Proceeds from the issuance of unsecured notes payable	0	400,000	0
Proceeds from the issuance of Common Stock	0	0	342,470
Payment of dividends to holders of Common Stock	(266,140)	(277,551)	(269,601)
Repurchases of Common Stock	(124,361)	(316,710)	0
Payment of distributions to common noncontrolling interests	(32,485)	(35,472)	(28,170)
Contributions from noncontrolling interests in consolidated real estate partnerships	5,691	9,206	7,458
Other financing activities, net	(37,254)	(19,395)	(20,794)
Net cash used in financing activities	(241,252)	(862,170)	(791,957)
NET (DECREASE) INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	(183,914)	208,644	19,281
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT BEGINNING OF PERIOD	301,405	92,761	73,480
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT END OF PERIOD	117,491	301,405	92,761
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid, net of amounts capitalized	128,431	114,340	130,202
Cash paid for income taxes	5,720	5,528	6,763
Non-cash transactions associated with the acquisition or disposition of real estate:
Non-recourse property debt assumed in connection with the acquisition of real estate	101,215	0	259,248
Issuance of common OP Units in connection with acquisition of real estate	22,383	0	121,557
Proceeds from investment in unconsolidated real estate partnerships for contribution of real estate	270,730	0	0
Other non-cash transactions:
Recognition of right-of-use lease assets	0	80,651	0
Recognition of lease liabilities	0	80,651	0
Accrued capital expenditures (at end of period)	5,287	10,701	9,732
Accrued share repurchases (at end of period)	24,595	0	0
Apartment Income REIT, L.P
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	689,287	970,050	479,224
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	342,593	350,945	319,742
Loss on extinguishment of debt	(2,008)	(23,636)	(156,707)
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	(677,740)	(939,806)	(594,861)
Income tax expense (benefit)	2,427	3,923	(5,246)
Share-based compensation expense	8,874	7,463	7,360
Other, net	29,231	3,195	7,230
Net changes in operating assets and operating liabilities:
Accounts receivable and other assets, net	5,338	27,864	(19,646)
Accounts payable, accrued liabilities and other	(31,618)	(26,713)	(17,554)
Total adjustments	(318,887)	(549,493)	(146,268)
Net cash provided by operating activities	370,400	420,557	332,956
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of real estate and deposits related to purchases of real estate	(346,626)	(861,320)	(364,055)
Capital expenditures	(173,662)	(192,404)	(174,499)
Contributions to unconsolidated real estate partnerships	(51,836)	0	0
Distributions from unconsolidated real estate partnerships	207,101	0	0
Proceeds from dispositions of real estate	52,066	1,209,241	915,926
Purchase of corporate assets	(15,862)	(13,940)	(5,171)
Proceeds from repayment of note receivable	0	534,127	0
Proceeds from investments in debt securities	0	0	100,852
Other investing activities, net	15,757	(25,447)	5,229
Net cash (used in) provided by investing activities	(313,062)	650,257	478,282
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from non-recourse property debt	1,005,920	54,156	0
Principal repayments on non-recourse property debt	(119,508)	(449,535)	(1,492,446)
Proceeds from term loans	0	0	1,150,000
Repayment of term loans	(325,000)	(350,000)	(350,000)
Net (repayments of) borrowings on revolving credit facility	(347,000)	159,205	36,756
Payment of debt extinguishment costs	(1,115)	(22,680)	(149,725)
Proceeds from the issuance of unsecured notes payable	0	400,000	0
Proceeds from the issuance of Common Stock	0	0	342,470
Payment of dividends to holders of Common Stock	(266,140)	(277,551)	(269,601)
Repurchases of Common Stock	(124,361)	(316,710)	0
Payment of distributions to common noncontrolling interests	(14,377)	(17,623)	(12,913)
Payment of distributions to Limited Partners	18,108	17,849	15,257
Redemptions of noncontrolling interests in the AIR Operating Partnership	0	(13,394)	(17,905)
Contributions from noncontrolling interests in consolidated real estate partnerships	5,691	9,206	7,458
Other financing activities, net	(37,254)	(19,395)	(20,794)
Net cash used in financing activities	(241,252)	(862,170)	(791,957)
NET (DECREASE) INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	(183,914)	208,644	19,281
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT BEGINNING OF PERIOD	301,405	92,761	73,480
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH AT END OF PERIOD	117,491	301,405	92,761
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid, net of amounts capitalized	128,431	114,340	130,202
Cash paid for income taxes	5,720	5,528	6,763
Non-cash transactions associated with the acquisition or disposition of real estate:
Non-recourse property debt assumed in connection with the acquisition of real estate	101,215	0	259,248
Issuance of common OP Units in connection with acquisition of real estate	22,383	0	121,557
Proceeds from investment in unconsolidated real estate partnerships for contribution of real estate	270,730	0	0
Other non-cash transactions:
Recognition of right-of-use lease assets	0	80,651	0
Recognition of lease liabilities	0	80,651	0
Accrued capital expenditures (at end of period)	5,287	10,701	9,732
Accrued share repurchases (at end of period)	$ 24,595	$ 0	$ 0

Basis of Presentation and Organ

Basis of Presentation and Organization	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Organization	Basis of Presentation and Organization Basis of Presentation The accompanying consolidated financial statements include the accounts of Apartment Income REIT Corp. (“AIR”), Apartment Income REIT, L.P. (“AIR Operating Partnership”), and their consolidated subsidiaries. The AIR Operating Partnership’s consolidated financial statements include the accounts of the AIR Operating Partnership and its consolidated subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. As used herein, and except where the context otherwise requires, “partnership” refers to a limited partnership or a limited liability company and “partner” refers to a partner in a limited partnership or a member of a limited liability company. Interests in the AIR Operating Partnership that are held by limited partners other than AIR are reflected in AIR’s accompanying consolidated balance sheets as noncontrolling interests in the AIR Operating Partnership. Interests in partnerships consolidated by the AIR Operating Partnership that are held by third parties are reflected in AIR’s and AIR Operating Partnership’s accompanying consolidated balance sheets as noncontrolling interests in consolidated real estate partnerships. Except as the context otherwise requires, “we,” “our,” and “us” refer to AIR, the AIR Operating Partnership, and their consolidated subsidiaries, collectively. Reclassifications Certain prior period balances in the consolidated balance sheets, statements of operations, and statements of cash flows have been combined or reclassified to conform to current period presentation. These changes had no impact on net income (loss), cash flows, assets and liabilities, equity or partners’ capital previously reported. Organization and Business AIR is a self-administered and self-managed REIT. AIR owns, through its wholly-owned subsidiaries, the general partner interest and special limited partner interest in AIR Operating Partnership. AIR Operating Partnership conducts all of the business of AIR, which is focused on the ownership of stabilized multi-family properties located in top markets including eight important geographic concentrations: Boston; Philadelphia; Washington, D.C.; Miami; Denver; the San Francisco Bay Area; Los Angeles; and San Diego. We own and operate a portfolio of apartment communities, diversified by both geography and price point, in 10 states and the District of Columbia. As of December 31, 2023, our portfolio included 75 apartment communities with 26,626 apartment homes, in which we held an average ownership of approximately 81%. Any references to the number of apartment communities and homes, square footage, or occupancy percentage in these notes to our consolidated financial statements are unaudited. Interests in the AIR Operating Partnership that are held by limited partners other than AIR are referred to as OP Units. OP Units include common partnership units, which we refer to as common OP Units, as well as preferred partnership units, which we refer to as preferred OP Units. As of December 31, 2023, after elimination of units held by consolidated subsidiaries, the AIR Operating Partnership had 159,130,441 common OP Units outstanding. As of December 31, 2023, AIR owned 144,925,604 of the common OP Units of the AIR Operating Partnership and AIR had an equal number of shares of its Class A Common Stock outstanding, which we refer to as Common Stock. AIR’s ownership of the total common OP Units outstanding represents 91.1% legal interest in the AIR Operating Partnership and a 93.6% economic interest.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Principles of Consolidation We consolidate variable interest entities (“VIE”), in which we are considered the primary beneficiary. The primary beneficiary is the entity that has (i) the power to direct the activities that most significantly impact the entity’s economic performance, and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could be significant to the VIE. As of December 31, 2023 and 2022, AIR consolidated five and seven VIEs, respectively, including the AIR Operating Partnership. Please see Note 15 for further discussion regarding our consolidated VIEs. Real Estate Acquisitions Upon the acquisition of real estate, we determine whether the purchase qualifies as an asset acquisition or meets the definition of an acquisition of a business. We generally recognize the acquisition of apartment communities or interests in partnerships that own communities at our cost, including the related transaction costs, as asset acquisitions. We allocate the cost of apartment communities acquired based on the relative fair value of the assets acquired and liabilities assumed. The fair value of these assets and liabilities is determined using valuation techniques that rely on Level 2 and Level 3 inputs within the fair value framework. We determine the fair value of tangible assets, such as land, buildings, furniture, fixtures, and equipment using valuation techniques that consider comparable market transactions, replacement costs, and other available information. We determine the fair value of identified intangible assets or liabilities, which typically relate to in-place leases, using valuation techniques that consider the terms of the in-place leases, current market data for comparable leases, and our experience in leasing similar communities. The intangible assets or liabilities related to in-place leases are comprised of: (a) the value of the above- and below-market leases in-place, measured over the period, including probable lease renewals for below-market leases, that the leases are expected to remain in effect; (b) the estimated unamortized portion of avoided leasing commissions and other costs that ordinarily would be incurred to originate the in-place leases; and (c) the value associated with leased apartment homes during an estimated absorption period, which estimates rental revenue that would not have been earned had leased apartment homes been vacant at the time of acquisition, assuming lease-up periods based on market demand and stabilized occupancy levels. The above- and below-market lease intangibles are amortized to rental revenue over the expected remaining terms of the associated leases, which include reasonably assured renewal periods. Other intangible assets related to in-place leases are amortized to depreciation and amortization over the expected remaining terms of the associated leases. Capital Additions We capitalize costs, including certain indirect costs, incurred in connection with our capital additions activities, including tangible apartment community improvements and replacements of existing apartment community components. Costs, including ordinary repairs, maintenance, and resident turnover costs, are charged to property operating expense as incurred. For the years ended December 31, 2023, 2022, and 2021, we capitalized to buildings and improvements $1.1 million, $1.5 million, and $2.4 million of interest costs, respectively, and $16.2 million, $16.6 million, and $10.3 million of other direct and indirect costs, respectively. Dispositions A property is classified as held for sale when all of the following criteria for a plan of sale have been met: (i) management, having the authority to approve the action, commits to a plan to sell the asset or disposal group; (ii) the asset or disposal group is available for immediate sale in its present condition, subject only to terms that are usual and customary; (iii) an active program to locate a buyer and other actions required to complete the plan to sell the asset or disposal group have been initiated; (iv) the sale of the asset or disposal group is probable and is expected to be completed within one year; (v) the asset or disposal group is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and (vi) actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn, which is typically indicated by receipt of all non-refundable deposits from the buyer pursuant to a sales contract. Depreciation of assets ceases upon designation of a property as held for sale. For sales of real estate, we evaluate whether the disposition represents a strategic shift that has, or will have, a major effect on our operations and financial results. If so, it is classified as discontinued operations in our consolidated financial statements for all periods presented. If not, it is presented in continuing operations in our consolidated financial statements. The disposal of an individual property generally will not represent a strategic shift that has a major effect, and therefore will typically not meet the criteria for classification as a discontinued operations. Gain or loss on real estate dispositions are recognized when we no longer hold a controlling financial interest in the real estate and sufficient consideration has been received. Upon disposition, the related assets and liabilities are derecognized, and the gain or loss on disposition is recognized as the difference between the carrying amount of those assets and liabilities and the value of consideration received. Impairment Real estate and other long-lived assets to be held and used are individually evaluated for impairment when conditions exist that may indicate the carrying amount of a long-lived asset may not be recoverable. We use the held for sale impairment model for properties classified as held for sale, whereby an impairment charge is recognized if the carrying amount of the long-lived asset classified as held for sale exceeds its fair value less cost to sell. If an impairment indicator exists, we compare the asset’s expected future undiscounted cash flows to its current carrying value to assess whether impairment measurement is necessary. Upon determination that an impairment has occurred, we recognize an impairment loss to the extent the carrying amount exceeds the estimated fair value of the real estate and other long-lived assets. During 2023, we recognized a non-cash impairment loss on real estate of $23.6 million. We did not recognize any such impairment during the years ended December 31, 2022 and 2021. The measurement of impairment is based on the fair value of the community and incorporates various estimates, assumptions, and market data, the most significant being rental rates, operating expense assumptions, expected hold period, capitalization rate, and purchase and sale agreements. We project future rental revenue growth rates using forecasted rates from third-party market research analytics. Property expense growth rates and capitalization rates are based on the apartment communities’ historical, current, and expected future operating results, existing operating expense assumptions, and operational strategies. These projections are adjusted to reflect current economic conditions and require considerable management judgment. Cash and Cash Equivalents We classify highly liquid investments with an original maturity of three months or less as cash equivalents. We maintain cash equivalents in financial institutions in excess of insured limits. We have not experienced any losses in these accounts in the past and believe that we are not exposed to significant credit risk because our accounts are deposited with major financial institutions. Restricted Cash As of December 31, 2023, restricted cash primarily consists of capital replacement reserves, completion repair reserves, real estate tax, insurance escrow accounts held by lenders, and resident security deposits. As of December 31, 2022, restricted cash primarily consists of cash deposited into 1031 exchange accounts in connection with tax-deferred exchange transactions that were released in conjunction with the Southgate Towers acquisition in January 2023 and the items above. Goodwill As of December 31, 2023 and 2022, goodwill associated with our reportable segments totaled $32.3 million. We perform an impairment test of goodwill annually, or when an interim triggering event occurs, by evaluating qualitative factors and quantitative factors, if necessary, to determine the likelihood that goodwill may be impaired. As a result of our annual impairment test, we determined that our goodwill was not impaired during the years ended December 31, 2023, 2022, and 2021. Other Assets, net As of December 31, 2023 and 2022, other assets, net was comprised of the following amounts (in thousands): 2023 2022 Mezzanine investment (1) $ — $ 158,726 Right-of-use lease assets 114,740 126,020 Other receivables, net 69,558 69,944 Other 99,622 195,131 Total other assets, net $ 283,920 $ 549,821 (1) Please see Note 15 Accrued Liabilities and Other As of December 31, 2023 and 2022, accrued liabilities and other was comprised of the following amounts (in thousands): 2023 2022 Mezzanine liability (1) $ — $ 158,726 Accrued expenses 234,679 225,888 Other 62,215 129,191 Total accrued liabilities and other $ 296,894 $ 513,805 (1) Please see Note 1 5 for further discussion regarding our Mezzanine liability. Investment in Unconsolidated Real Estate Partnerships We may own general and limited partner interests in partnerships that either directly, or through interests in other real estate partnerships, own apartment communities. We generally account for investments in real estate partnerships that we do not consolidate under the equity method. Under the equity method, we recognize our share of the earnings or losses of the entity for the periods presented, inclusive of our share of any impairments and disposition gains or losses recognized by and related to such entities, and we present such amounts within income from unconsolidated real estate partnerships in our consolidated statements of operations. Investment in unconsolidated real estate partnerships is included as a separate line item in our consolidated balance sheets. Investments in unconsolidated real estate partnerships are reviewed for impairments. An impairment loss is recorded when there is a decline in the fair value below the carrying value and we conclude such decline is other-than-temporary. An impairment loss is measured based on the excess of the carrying amount of an investment over its estimated fair value. We determine the fair value of investments in unconsolidated real estate partnerships using valuation techniques that consider the terms of the in-place leases, current market data for comparable leases, our experience in leasing similar communities, and current plans. We recognized no such impairments for any of the years ended December 31, 2023, 2022, and 2021. The excess of our cost of the acquired partnership interests over our share of the partners’ equity or deficit are included as a part of our investments in unconsolidated real estate partnerships. We amortize the excess cost over the term of the joint venture agreement. The amortization is recorded as an adjustment of the amounts of earnings or losses we recognize from such unconsolidated real estate partnerships. Please see Note 6 for further discussion regarding our investment in unconsolidated real estate partnerships. Noncontrolling Interests in Consolidated Real Estate Partnerships We generally report the unaffiliated partners’ interests in the net assets of our consolidated real estate partnerships as noncontrolling interests in consolidated real estate partnerships within consolidated equity and partners’ capital. If a real estate partnership includes redemption rights that are not within AIR and the AIR Operating Partnership’s control, the noncontrolling interest is included as temporary equity or temporary capital. The assets of real estate partnerships consolidated by the AIR Operating Partnership must first be used to settle the liabilities of such consolidated real estate partnerships. These consolidated real estate partnerships’ creditors do not have recourse to the general credit of the AIR Operating Partnership. Noncontrolling interests in consolidated real estate partnerships consist primarily of equity interests held by limited partners in consolidated real estate partnerships that have finite lives. We generally attribute to noncontrolling interests their share of income or loss of consolidated partnerships based on their proportionate interest in the results of operations of the partnerships, including their share of losses even if such attribution results in a deficit noncontrolling interest balance within our equity and partners’ capital accounts. The terms of the related partnership agreements generally require the partnerships to be liquidated following the sale of the underlying real estate. As the general partner in these partnerships, we ordinarily control the execution of real estate sales and other events that could lead to the liquidation, redemption or other settlement of noncontrolling interests. Changes in our ownership interest in consolidated real estate partnerships generally consist of our purchase of an additional interest in or the sale of our entire or partial interest in a consolidated real estate partnership. The effect on our equity and partners’ capital of our purchase of additional interests in consolidated real estate partnerships during the years ended December 31, 2023, 2022, and 2021, is shown in our consolidated statements of equity and partners’ capital. The effect on our equity and partners’ capital of sales of consolidated real estate or sales of our entire interest in consolidated real estate partnerships is reflected in our consolidated statements of operations as gains or losses on dispositions of real estate and accordingly the effect on our equity and partners’ capital is reflected within the amount of net income allocated to us and to noncontrolling interests. Upon our deconsolidation of a real estate partnership following the sale of our partnership interests or liquidation of the partnership following sale of the related apartment community, we derecognize any remaining noncontrolling interest of the associated partnership previously recorded in our consolidated balance sheets. Noncontrolling Interests in the AIR Operating Partnership Noncontrolling interests in the AIR Operating Partnership consist of common OP Units and preferred OP Units and are reflected in AIR’s accompanying consolidated balance sheets as noncontrolling interests in AIR Operating Partnership. Holders of preferred OP Units participate in the AIR Operating Partnership’s income or loss only to the extent of their preferred distributions. Within AIR’s consolidated financial statements, after provision for preferred OP Unit distributions, the AIR Operating Partnership’s income or loss is allocated to the holders of common OP Units based on the weighted-average number of common OP Units (including those held by AIR) outstanding during the period. During the years ended December 31, 2023, 2022, and 2021, the holders of common OP Units (excluding those held by AIR) had a weighted-average economic ownership interest in the AIR Operating Partnership of 6.37%, 6.25%, and 6.07%, respectively. Please refer to Note 9 for further information regarding the items comprising noncontrolling interests in the AIR Operating Partnership. Substantially all of the assets and liabilities of AIR are those of the AIR Operating Partnership. Revenue from Leases We are a lessor primarily for residential leases. Our operating leases with residents may also provide that the resident reimburse us for certain costs, primarily the resident’s share of utilities expenses, incurred by the apartment community. These reimbursements represent revenue attributable to nonlease components for which the timing and pattern of recognition is the same as the revenue for the lease components. We use the practical expedient that allows us to account for the lease and nonlease components as a single component. Reimbursement and related expense are presented on a gross basis in our consolidated statements of operations, with the reimbursement included in rental and other property revenues attributable to real estate in our consolidated statements of operations. We recognize rental revenue attributed to lease components, net of any concessions, on a straight-line basis over the term of the lease. Insurance We believe our insurance coverages insure our apartment communities adequately against the risk of loss attributable to fire, earthquake, hurricane, tornado, flood, and other perils. In addition, we have third-party insurance coverage (after self-insured retentions) that defray the costs of large workers’ compensation, health, and general liability exposures. We accrue losses based upon our estimates of the aggregate liability for uninsured losses incurred using certain actuarial assumptions followed in the insurance industry and based on our experience. Depreciation and Amortization Depreciation for all tangible assets is calculated using the straight-line method over their estimated useful life. Acquired buildings and improvements are depreciated over a useful life based on the age, condition, and other physical characteristics of the asset. Furniture, fixtures, and equipment are generally depreciated over five years. We depreciate capitalized costs using the straight-line method over the estimated useful life of the related improvement, which is generally 5, 15, or 30 years. Purchased software and other costs related to software purchased or developed for internal use are capitalized during the application development stage and are amortized using the straight-line method over the estimated useful life of the software, generally three Certain homogeneous items that are purchased in bulk on a recurring basis, such as appliances, are depreciated using group methods that reflect the average estimated useful life of the items in each group. Except in the case of apartment community casualties, where the net book value of the lost asset is written off in the determination of casualty gains or losses, we generally do not recognize any loss in connection with the replacement of an existing apartment community component because normal replacements are considered in determining the estimated useful life used in connection with our composite and group depreciation methods. Share-Based Compensation We issue various forms of share-based compensation, including stock options and restricted stock awards with service, performance or market conditions. We recognize share-based employee compensation based on the fair value on the grant date and recognize compensation cost over the awards’ requisite service periods. We reduce compensation cost related to forfeited awards in the period of forfeiture. Please refer to Note 10 for further discussion of our share-based compensation. Income Taxes AIR has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”), commencing with its taxable year ended December 31, 2020, and it intends to continue to operate in such a manner. AIR’s current and continuing qualification as a REIT depends on its ability to meet the various requirements imposed by the Code, which are related to organizational structure, distribution levels, diversity of stock ownership, and certain restrictions with regard to owned assets and categories of income. As a REIT, we are generally not subject to federal and certain state income tax on the net income that we currently distribute to stockholders. This treatment substantially eliminates the “double taxation” (at the corporate and stockholder levels) that generally results from an investment in a corporation. Even if AIR qualifies as a REIT, it may be subject to United States federal income and excise taxes in various situations, such as on undistributed income. AIR could also be subject to a 100% tax on transactions between it and a TRS (described below) that are determined to be non-arm’s length and on any net income from sales of apartment communities that are determined to be dealer-type prohibited transactions. The state and local tax laws may not conform to the United States federal income tax treatment, and AIR may be subject to state or local taxation in various state or local jurisdictions, including those in which we transact business. Any taxes imposed on us reduce our operating cash flow and net income. Certain of AIR’s operations, or a portion thereof, including property management and risk management, are conducted through taxable REIT subsidiaries, which are subsidiaries of the AIR Operating Partnership, and each of which we refer to as a TRS. A TRS is a corporate subsidiary that has elected to be a TRS instead of a REIT and, as such, is subject to United States federal corporate income tax. We use TRS entities to facilitate our ability to offer certain services and activities to our residents and investment partners that cannot be offered directly by a REIT. For our TRS entities, deferred income taxes result from temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts reported for United States federal income tax purposes, and are measured using the enacted tax rates and laws that are expected to be in effect when the differences reverse. We reduce deferred tax assets by recording a valuation allowance when we determine, based on available evidence, that it is more likely than not that the assets will not be realized. We recognize the tax consequences associated with intercompany transfers between the AIR Operating Partnership and TRS entities when such transactions occur. Please refer to Note 11 for further information about our income taxes. Earnings per Share and Unit AIR and the AIR Operating Partnership calculate earnings per share and unit, respectively, based on the weighted-average number of shares of Common Stock or common OP units, participating securities, Common Stock or common unit equivalents, and dilutive convertible securities outstanding during the period. The AIR Operating Partnership considers both common OP units and equivalents, which have identical rights to distributions and undistributed earnings, to be common units for purposes of the earnings per unit computations. Please refer to Note 12 for further information regarding earnings per share and unit computations. Use of Estimates The preparation of our consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts included in the consolidated financial statements and accompanying notes thereto. Actual results could differ from those estimates. Accounting Pronouncements Recently Issued In November 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2023-07, “Segment Reporting – Improvements to Reportable Segments Disclosures.” The amendments enhance disclosures of significant segment expenses by requiring to disclose significant segment expenses regularly provided to the chief operating decision maker ("CODM"), extend certain annual disclosures to interim periods, and permit more than one measure of segment profit or loss to be reported under certain conditions. The amendments are effective for AIR in fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption of the amendment is permitted, including adoption in any interim periods for which financial statements have not been issued. AIR is currently evaluating the guidance and its impact to the consolidated financial statements. In December 2023, the FASB issued ASU No. 2023-09, "Improvements to Income Tax Disclosures," which requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as information on income taxes paid. The standard is intended to benefit investors by providing more detailed income tax disclosures that would be useful in making capital allocation decisions. This ASU is effective for public companies with annual periods beginning after December 15, 2024, with early adoption permitted. AIR is currently evaluating the guidance and its impact to the consolidated financial statements. Accounting standards that have been issued by the FASB, or other standards-setting bodies, that are not yet effective or discussed above are not expected to have a material impact on the Company’s consolidated financial statements upon adoption.

Significant Transactions

Significant Transactions	12 Months Ended
	Dec. 31, 2023
Significant Transactions [Abstract]
Significant Transactions	Significant Transactions Apartment Community Acquisitions During the year ended December 31, 2023, we acquired one apartment community located in Raleigh, North Carolina, one apartment community located in Durham, North Carolina, and one apartment community located in Miami Beach, Florida. Summarized information regarding these acquisitions is set forth in the table below (dollars in thousands) as of December 31, 2023: Number of apartment communities 3 Number of apartment homes 1,115 Purchase price $ 452,500 Capitalized transaction costs 6,739 Total consideration (1) $ 459,239 Land $ 118,564 Building and improvements 318,364 Intangible assets (2) 17,845 Mark-to-market on debt assumed 7,370 Below-market lease liabilities (2) (2,904) Total consideration (1) $ 459,239 (1) Total consideration for the apartment community acquisition in South Florida includes $101.2 million of debt assumed and the issuance of $22.4 million in common OP Units, which represent non-cash financing. (2) Intangible assets and below-market lease liabilities for the South Florida apartment community acquisition have a weighted-average term of 1.4 years and 0.5 years, respectively. Intangible assets and below-market lease liabilities for the North Carolina apartment community acquisitions have a weighted-average term of 0.5 years. Subsequent to the year ended December 31, 2023, we acquired one apartment community located in Raleigh, North Carolina with 384 apartment homes for $86.5 million. Apartment Community Dispositions Sold apartment communities during the years ended December 31, 2023, 2022, and 2021, are summarized below (dollars in thousands): 2023 2022 2021 Number of apartment communities sold 3 18 16 Number of apartment homes sold 257 3,364 1,395 Gain on apartment community sales (1) $ — $ 939,806 $ 243,369 (1) The apartment communities sold during the year ended December 31, 2023 generated net proceeds of $52.1 million, which approximated their carrying value. The apartment communities sold were predominantly located outside of primary markets or in lower-rated locations within primary markets and had average revenues per apartment home significantly below those of our retained portfolio. At the end of each reporting period we evaluate whether any communities meet the criteria to be classified as held for sale. As of December 31, 2023, no communities were classified as held for sale. Lease Cancellation During 2021, we leased certain properties for the purpose of their development, which were accounted for as sales-type leases. During the years ended December 31, 2022 and 2021, we recognized income of $17.3 million and $26.0 million, respectively, related to these sales-type leases, which is reflected in interest income in our consolidated statements of operations. During the year ended December 31, 2023, we did not recognize any income as the sales-type leases were cancelled on September 1, 2022. Impairment Real estate and other long-lived assets to be held and used are individually evaluated for impairment when conditions exist that may indicate the carrying amount of a long-lived asset may not be recoverable. Impairment indicators include significant fluctuations in rental and other property revenues less property operating expenses, occupancy changes, significant near-term lease expirations, current and historical cash flow losses, rental rates, and if applicable, a comparison of an asset’s carrying value to its estimated fair value. Upon determination that an impairment has occurred, we recognize an impairment loss to the extent the carrying amount exceeds the estimated fair value of the community. As part of our exit from the New York market, during the year ended December 31, 2023, we evaluated the expected hold period of three apartment communities in our Other Real Estate reporting segment. Given management's assessment of the likelihood of the sale of these assets, which occurred during the year ended December 31, 2023, we reduced the carrying value of the three properties to their estimated fair value and recognized a non-cash impairment loss on real estate of $23.6 million. As of December 31, 2023, the three impaired properties have been sold. During the years ended December 31, 2022 and 2021, we did not recognize any impairment losses. Note Receivable from Aimco In 2020, we acquired a $534 million note receivable (the “Note”) pledged by a subsidiary of Aimco and was secured by a pool of properties owned by Aimco. The Note had an original maturity date of January 31, 2024, and bore interest at a rate of 5.2% per annum. The Note was reported at the outstanding principal balance, and interest receivable related to the unpaid principal was recorded separately in other assets, net in our consolidated balance sheets. The note was prepaid in 2022 and we recognized interest income of $13.8 million, and $27.8 million, during the years ended December 31, 2022, and 2021, respectively.

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leases	Leases Tenant Lessor Arrangements The majority of lease payments we receive from our residents are fixed. We receive variable payments from our residents primarily for utility reimbursements. Our total lease income was comprised of the following amounts for all operating leases for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Fixed lease income $ 752,068 $ 715,060 $ 685,423 Variable lease income 56,060 47,358 46,246 Total lease income $ 808,128 $ 762,418 $ 731,669 Generally, our residential leases do not provide extension options and, as of December 31, 2023, have an average remaining term of 8.7 months. In general, our commercial leases have options to extend for a certain period of time at the tenant’s option. As of December 31, 2023, future minimum annual rental payments we are contractually obligated to receive under residential and commercial leases, excluding such extension options, are as follows (in thousands): 2024 $ 420,571 2025 85,348 2026 12,975 2027 11,066 2028 9,411 Thereafter 30,685 Total $ 570,056 Lessee Arrangements We recognize right-of-use assets and related lease liabilities, which are included in other assets, net and accrued liabilities and other, respectively, in our consolidated balance sheets. We estimated the value of the lease liabilities using a discount rate equivalent to the rate we would pay on a secured borrowing with similar terms to the lease. Substantially all of the payments under our ground and office leases are fixed. We exclude options to extend the lease in our minimum lease terms unless the option is reasonably certain to be exercised. During 2022, we assumed a ground lease for a property acquired in the Washington, D.C. area. Our total lease cost for ground and office leases for the years ended December 31, 2023, 2022, and 2021 was $21.5 million, $15.4 million, and $5.3 million, respectively. As of December 31, 2023, the ground and office leases have weighted-average remaining terms of 88.0 and 5.2 years, respectively, and weighted-average discount rates of 6.8% and 3.8%, respectively. As of December 31, 2023, minimum annual rental payments under these operating leases, reconciled to the lease liability included in accrued liabilities and other in our consolidated balance sheets, are as follows (in thousands): 2024 $ 8,053 2025 8,084 2026 8,390 2027 8,344 2028 20,945 Thereafter 1,695,808 Total 1,749,624 Less: Discount 1,613,987 Total lease liability $ 135,637 Of the total lease liability as of December 31, 2023, $128.1 million of the balance relates to our ground leases, with the remainder relating to our office leases.
Lessee, Operating Leases	Leases Tenant Lessor Arrangements The majority of lease payments we receive from our residents are fixed. We receive variable payments from our residents primarily for utility reimbursements. Our total lease income was comprised of the following amounts for all operating leases for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Fixed lease income $ 752,068 $ 715,060 $ 685,423 Variable lease income 56,060 47,358 46,246 Total lease income $ 808,128 $ 762,418 $ 731,669 Generally, our residential leases do not provide extension options and, as of December 31, 2023, have an average remaining term of 8.7 months. In general, our commercial leases have options to extend for a certain period of time at the tenant’s option. As of December 31, 2023, future minimum annual rental payments we are contractually obligated to receive under residential and commercial leases, excluding such extension options, are as follows (in thousands): 2024 $ 420,571 2025 85,348 2026 12,975 2027 11,066 2028 9,411 Thereafter 30,685 Total $ 570,056 Lessee Arrangements We recognize right-of-use assets and related lease liabilities, which are included in other assets, net and accrued liabilities and other, respectively, in our consolidated balance sheets. We estimated the value of the lease liabilities using a discount rate equivalent to the rate we would pay on a secured borrowing with similar terms to the lease. Substantially all of the payments under our ground and office leases are fixed. We exclude options to extend the lease in our minimum lease terms unless the option is reasonably certain to be exercised. During 2022, we assumed a ground lease for a property acquired in the Washington, D.C. area. Our total lease cost for ground and office leases for the years ended December 31, 2023, 2022, and 2021 was $21.5 million, $15.4 million, and $5.3 million, respectively. As of December 31, 2023, the ground and office leases have weighted-average remaining terms of 88.0 and 5.2 years, respectively, and weighted-average discount rates of 6.8% and 3.8%, respectively. As of December 31, 2023, minimum annual rental payments under these operating leases, reconciled to the lease liability included in accrued liabilities and other in our consolidated balance sheets, are as follows (in thousands): 2024 $ 8,053 2025 8,084 2026 8,390 2027 8,344 2028 20,945 Thereafter 1,695,808 Total 1,749,624 Less: Discount 1,613,987 Total lease liability $ 135,637 Of the total lease liability as of December 31, 2023, $128.1 million of the balance relates to our ground leases, with the remainder relating to our office leases.

Debt

Debt	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Debt	Debt The following table summarizes our total consolidated indebtedness as of December 31, 2023 and 2022 (in thousands): 2023 2022 Secured debt: Fixed-rate property debt due May 2025 to January 2055 (1) $ 2,236,975 $ 1,906,151 Variable-rate property debt — 88,500 Total non-recourse property debt 2,236,975 1,994,651 Debt issuance costs, net of accumulated amortization (13,184) (9,221) Total non-recourse property debt, net $ 2,223,791 $ 1,985,430 Unsecured debt: Term loans due December 2024 to April 2026 (2) 475,000 800,000 Revolving credit facility borrowings due April 2025 (3) 115,000 462,000 4.58% Notes payable due June 2027 100,000 100,000 4.77% Notes payable due June 2029 100,000 100,000 4.84% Notes payable due June 2032 200,000 200,000 Total unsecured debt 990,000 1,662,000 Debt issuance costs, net of accumulated amortization (3,447) (5,801) Total unsecured debt, net 986,553 1,656,199 Total indebtedness $ 3,210,344 $ 3,641,629 (1) In the first quarter of 2023, AIR borrowed $320 million using 10-year fixed rate financing, bearing interest at 4.9%. Proceeds were used to refinance a floating rate loan and reduce borrowings by $230 million on our revolving credit facility. The stated rates on our fixed-rate property debt are between 2.7% to 5.7%. (2) The term loans bear interest at a one-month Term Secured Overnight Financing Rate (“SOFR”) plus 1.00% and a SOFR adjustment of 10-basis points, based on our current credit rating. As of December 31, 2023, the weighted-average interest rate for our term loans before consideration of in place interest rate swaps was 6.5%. As of December 31, 2023, our entire $475 million term loan balance is fixed via interest rate swaps at a weighted-average interest rate of 4.3%. The term loans mature on the following schedule: $125 million matures on December 15, 2024, with a one (3) As of December 31, 2023, we had capacity to borrow up to $880.7 million under our revolving credit facility after consideration of undrawn letters of credit. The revolving credit facility bears interest at a one-month Term SOFR plus 0.89%, based on our current credit rating, and a SOFR adjustment of 10-basis points. As of December 31, 2023, the weighted-average interest rate for our revolving credit facility was 6.3%. Subsequent to the year ended December 31, 2023, we entered into interest rate swaps economically hedging $200 million of our revolving credit facility borrowings at 4.9%. In April 2023, we established a secured credit facility that provides for up to $1 billion of committed property level financing, on an as needed basis. The facility has a 15-year term, and provides AIR the opportunity to place up to 10-year non-recourse property debt financing. Pricing can be fixed rate or variable rate at AIR's choice and is based on the Fannie Mae grid. During the third quarter of 2023, AIR placed $611.4 million in new fixed-rate property debt related to nine properties, which was subsequently contributed to the Core JV. Additionally, one property with $33.0 million in fixed-rate property debt was also contributed to the Core JV, for a total of $644.4 million of debt contributed. As the Core JV is unconsolidated, this fixed-rate property debt is excluded from our consolidated balance sheet as of December 31, 2023. During the third quarter of 2023, AIR refinanced $325 million of term loans with fixed rate property debt to lock in rates for debt with longer maturities. The amount included full repayment of $150 million of our term loans with a maturity of December 15, 2023 and partial repayment of $175 million of term loans with a maturity of December 15, 2024. In conjunction with the prepayment, AIR accelerated recognition of $0.8 million of associated debt issuance costs, which is included in interest expense in our consolidated statements of operations. As of December 31, 2023, and after consideration of the secured credit facility, total liquidity is approximately $1.9 billion. As of December 31, 2023, our fixed-rate property debt was secured by 26 apartment communities that had an aggregate net book value of $2.5 billion. AIR did not have any consolidated variable-rate property debt as of December 31, 2023. Principal and interest on fixed-rate property debt are generally payable monthly or in monthly interest-only payments with balloon payments due at maturity. As of December 31, 2023, the scheduled principal amortization and maturity payments for our outstanding debt balances were as follows (in thousands): Amortization Maturities Total 2024 (1) $ 31,823 $ — $ 31,823 2025 (1) (2) 29,146 646,323 675,469 2026 (1) 23,625 361,950 385,575 2027 21,071 163,098 184,169 2028 15,537 189,652 205,189 Thereafter 189,352 1,440,398 1,629,750 Total $ 310,554 $ 2,801,421 $ 3,111,975 (1) Amounts presented above are inclusive of extension options on our terms loans, as outlined above. (2) The table above excludes our revolving credit facility due April 2025, which had an outstanding balance of $115.0 million as of December 31, 2023.

Investments in Unconsolidated R

Investments in Unconsolidated Real Estate Partnerships	12 Months Ended
	Dec. 31, 2023
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Real Estate Partnerships	Investment in Unconsolidated Real Estate Partnerships Joint Venture Transactions AIR formed two joint ventures in 2023. The first, the Value-Add JV, was formed by contributing the Huntington Gateway property, a 443-unit property located in Virginia in exchange for $9 million in cash and the assumption by the joint venture of $94.1 million in debt, which represents non-cash financing activity during the period. AIR is the general partner and retains legal ownership of 30%, and receives 50% of the net cash flows from operations, and various fees for providing property management, construction, and corporate services to the joint venture. We recognized a gain of $1.0 million in connection with this transaction during the year ended December 31, 2023. We formed the Core JV by contributing 10 properties located in Philadelphia, PA, Washington, D.C. area, Denver, CO, Oceanside, CA, and Kendall, FL. The Core JV, in which we retain a 53% interest, closed with respect to (i) eight of the properties in July 2023, (ii) one property in August 2023, and (iii) one property in September 2023. The 10 properties, with a total fair value of $1.1 billion and a carrying value of $373.3 million, were contributed to the Core JV subject to $644.4 million of non-recourse property debt, which represents a non-cash financing activity during the period. In advance of the joint venture closing, AIR placed $611.4 million in new non-recourse property debt, which was subsequently contributed to the joint venture. As a result of the transaction, AIR received $201.9 million in cash and recognized a gain of $700.5 million, including the measurement of the fair value of our interest in the Core JV during the year ended December 31, 2023. AIR will earn various fees for providing property management, construction, and corporate services to the joint venture. Additionally, in the third quarter of 2023, AIR and our joint venture partner increased the investment in the Core JV to fund the joint venture's acquisition of an 11th property, a 456-unit property located in Bethesda, Maryland. The Core JV funded the acquisition with $155.0 million in new debt, and capital contributions to the joint venture of $95.0 million, for a purchase price of $250.0 million. AIR has a 53% ownership in the joint venture's acquisition of the eleventh property. Unconsolidated Joint Ventures As of December 31, 2023, AIR has equity investments in three significant unconsolidated joint ventures: the Core JV, the Value-Add JV, and the Virginia JV (collectively, the "Joint Venture Entities"). We account for these joint ventures using the equity method of accounting and our ownership interests meet the definition of a VIE. However, we are not the primary beneficiary and do not consolidate these entities. Virginia JV Value-Add JV (1) Core JV Initial formation date October 2021 June 2023 July 2023 AIR Ownership 20% 30% 53% Outside entities ownership 80% 70% 47% Number of apartment communities 3 1 11 Apartment units 1,748 443 3,549 (1) The purchaser acquired a 70% legal ownership in the Huntington Gateway property, but AIR is entitled to 50% of the net cash flows from operations, and various fees for providing property management, construction, and corporate services to the joint venture. The carrying value of AIR's investment in each joint venture is included in investment in unconsolidated real estate partnerships in our consolidated balance sheets. AIR's exposure to the obligations of the VIEs is limited to the carrying value of the limited partnership interests and AIR's interest of the joint ventures' guarantor non-recourse liabilities. The following table summarizes certain relevant financial information with respect to our investment in unconsolidated joint ventures (in thousands): December 31, 2023 Virginia JV Value-Add JV Core JV Net real estate $ 467,020 $ 131,339 $ 1,258,307 Other assets, net 7,061 7,368 41,882 Total assets $ 474,081 $ 138,707 $ 1,300,189 Third-party debt $ 395,000 $ 88,741 $ 793,910 Accrued liabilities and other 4,070 2,528 10,298 Total liabilities $ 399,070 $ 91,269 $ 804,208 Total equity $ 75,011 $ 47,438 $ 495,981 AIR's investment in balance (1) $ 17,212 $ 28,606 $ 268,931 (1) AIR's investment in balance includes certain basis differences that are subject to amortization. AIR's investment in unconsolidated real estate partnerships in our consolidated balance sheets also includes $21.3 million related to two immaterial unconsolidated investments. December 31, 2022 Virginia JV Value-Add JV Core JV Net real estate $ 481,939 $ — $ — Other assets, net 10,841 — — Total assets $ 492,780 $ — $ — Third-party debt $ 395,000 $ — $ — Accrued liabilities and other 5,179 — — Total liabilities $ 400,179 $ — $ — Total equity $ 92,601 $ — $ — AIR's investment in balance (1) $ 20,684 $ — $ — (1) AIR's investment in unconsolidated real estate partnerships in our consolidated balance sheets includes $21.2 million related to two immaterial unconsolidated investments. The following tables summarize the financial information related to the Joint Venture Entities for the years ended December 31, 2023, 2022, and 2021 (in thousands): December 31, 2023 Virginia JV Value-Add JV Core JV Total revenues $ 44,725 $ 6,665 $ 51,341 Total expenses 64,779 12,969 94,141 Net loss $ (20,054) $ (6,304) $ (42,800) AIR's loss from unconsolidated real estate partnerships $ (3,999) $ (2,772) $ (22,877) December 31, 2022 Virginia JV Value-Add JV Core JV Total revenues $ 41,422 $ — $ — Total expenses 57,316 — — Net loss $ (15,894) $ — $ — AIR's loss from unconsolidated real estate partnerships $ (3,504) $ — $ — December 31, 2021 Virginia JV Value-Add JV Core JV Total revenues $ 7,471 $ — $ — Total expenses 11,414 — — Net loss $ (3,943) $ — $ — AIR's loss from unconsolidated real estate partnerships $ (565) $ — $ —

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments We enter into certain commitments for future purchases of goods and services in connection with the operations of our apartment communities. Those commitments generally have terms of one year or less and reflect expenditure levels comparable to our historical expenditures. Legal Matters In addition to the matters described below, we are a party to various legal actions and administrative proceedings arising in the ordinary course of business, some of which are covered by our general liability insurance program, and none of which we expect to have a material adverse effect on our consolidated financial condition, results of operations or cash flows. Environmental Various federal, state and local laws subject apartment community owners or operators to liability for management and the costs of removal or remediation of certain potentially hazardous materials that may be present in the land or buildings of an apartment community. Such laws often impose liability without regard to fault or whether the owner or operator knew of, or was responsible for, the presence of such materials. The presence of, or the failure to manage or remediate properly, these materials may adversely affect occupancy at such apartment communities as well as the ability to sell or finance such apartment communities. In addition, governmental agencies may bring claims for costs associated with investigation and remediation actions. Moreover, private plaintiffs may potentially make claims for investigation and remediation costs they incur or for personal injury, disease, disability, or other infirmities related to the alleged presence of hazardous materials. In addition to potential environmental liabilities or costs associated with our current apartment communities, we may also be responsible for such liabilities or costs associated with communities we acquire or manage in the future or apartment communities we no longer own or operate. We are engaged in discussions with the Environmental Protection Agency (“EPA”), regarding contaminated groundwater near an Indiana apartment community that has not been owned by us since 2008, for which we have recognized a contingent liability. The contamination allegedly derives from a dry cleaner that operated on our former property, prior to our ownership. We undertook a voluntary remediation of the dry cleaner contamination under state oversight. In 2016, EPA listed our former community and a number of residential communities in the vicinity on the National Priorities List (“NPL”) (i.e., as a Superfund site). In May 2018, we prevailed on our federal judicial appeal vacating the Superfund listing. We continue to work with EPA to formulate an agreed order to reimburse EPA costs and finish clean-up of the site outside the Superfund program. Although the outcome of this process is uncertain, we do not expect the resolution to have a material adverse effect on our consolidated financial condition, results of operations, or cash flows. We have a contingent liability related to a property in Lake Tahoe, California. An entity owned by us was the former general partner of a now-dissolved partnership that previously owned a site where a laundromat, with a self-service dry-cleaning machine, operated. That entity and the current property owner have been remediating the site since 2009, under the oversight of the Lahontan Regional Water Quality Control Board (“Lahontan”). In May 2017, Lahontan issued a final cleanup and abatement order that names four potentially-responsible parties, acknowledges that there may be additional responsible parties, and requires the named parties to perform additional groundwater investigation and corrective actions with respect to onsite and offsite contamination. We appealed the final order, and on June 1, 2020, the court vacated the Order against us. However, there are still civil suits pending related to this contingent liability. Although the outcome of this process is uncertain, we do not expect the resolution to have a material adverse effect on our consolidated financial condition, results of operations, or cash flows. We have determined that our legal obligations to remove or remediate certain potentially hazardous materials may be conditional asset retirement obligations (“AROs”), as defined by GAAP. Except in limited circumstances where the asset retirement activities are expected to be performed in connection with a planned construction project or apartment community casualty, we believe that the fair value of our AROs cannot be reasonably estimated due to significant uncertainties in the timing and manner of settlement of those obligations. AROs that are reasonably estimable as of December 31, 2023, are immaterial to our consolidated financial statements.

AIR Equity

AIR Equity	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
AIR Equity	AIR Equity Common Stock During the years ended December 31, 2023, 2022, and 2021, we declared regular, recurring cash dividends per common share of $1.80, $1.80, and $1.74, respectively. Share Repurchases During the year ended December 31, 2023, we repurchased 4.3 million shares of Common Stock for $149.0 million, at an average price of $34.48. Subsequent to year ended December 31, 2023, AIR's Board of Directors authorized an additional $500 million of share repurchases, which replaced the remaining $34.3 million balance under the previous share repurchase authorization. We consider share buybacks as part of a balanced investment program. Equity Issuance On April 23, 2021, we issued and sold 7.8 million shares of our Class A Common Stock for $43.77 per share in a private placement to a large global real estate-focused investment firm and received cash proceeds of $342.2 million, net of fees. Proceeds raised were used to repay $318.4 million of property debt with a weighted-average interest rate of 4.6%. Preferred Stock As of December 31, 2023 and 2022, we had a single class of perpetual Preferred Stock outstanding, our Class A Preferred Stock, with 20 shares issued and outstanding and a balance of $2.0 million. Our Class A Preferred Stock has a $0.01 per share par value, is senior to our Common Stock, has a liquidation preference per share of $100,000, and is redeemable at our option on or after December 15, 2025. The holders of our Class A Preferred Stock are generally not entitled to vote on matters submitted to stockholders. Dividends in an amount per share equal to 8.5% per annum are subject to declaration by our Board of Directors.

Partners' Capital

Partners' Capital	12 Months Ended
	Dec. 31, 2023
Partners' Capital [Abstract]
Partners' Capital	Partners’ Capital Partnership Preferred Units Owned by AIR At December 31, 2023 and 2022, the AIR Operating Partnership had Class A outstanding preferred units similar to AIR’s Preferred Stock discussed in Note 8 . All Class A Partnership Preferred Units are senior to the AIR Operating Partnership common partnership units. Distributions on all Partnership Preferred Units are subject to being declared by the General Partner. The Partnership Preferred Units are redeemable by the AIR Operating Partnership only in connection with a concurrent redemption by AIR of the corresponding AIR Preferred Stock held by unrelated parties. Redeemable Preferred OP Units The AIR Operating Partnership has outstanding various classes of redeemable preferred OP Units. As of December 31, 2023 and 2022, the AIR Operating Partnership had the following classes of preferred OP Units (stated at their redemption values, in thousands, except unit and per unit data): Distributions per Annum Units Issued and Redemption Values Class of Preferred Units Percent Per Unit 2023 2022 2023 2022 Class One 8.75 % $ 8.00 90,000 90,000 $ 8,229 $ 8,229 Class Two 1.92 % $ 0.48 5,368 5,418 132 135 Class Three 7.88 % $ 1.97 1,310,902 1,310,902 32,772 32,772 Class Four 8.00 % $ 2.00 644,954 644,954 16,124 16,124 Class Six 8.50 % $ 2.13 769,585 769,585 19,240 19,240 Class Seven 7.87 % $ 1.97 25,715 25,715 643 643 Total 2,846,524 2,846,574 $ 77,140 $ 77,143 Each class of preferred OP Units is currently redeemable at the holders’ option. The AIR Operating Partnership, at its sole discretion, may settle such redemption requests in cash or cause AIR to issue shares of its Common Stock with a value equal to the redemption price. In the event the AIR Operating Partnership requires AIR to issue shares of Common Stock to settle a redemption request, the AIR Operating Partnership would issue to AIR a corresponding number of common OP Units. The AIR Operating Partnership has a redemption policy that requires cash settlement of redemption requests for the preferred OP Units, subject to limited exceptions. Subject to certain conditions, the Class Four and Class Six preferred OP Units may be converted into common OP Units. These redeemable preferred units are classified within temporary equity in AIR’s consolidated balance sheets and within temporary capital in the AIR Operating Partnership’s consolidated balance sheets. During the years ended December 31, 2023, 2022, and 2021, approximately 50, 89,000, and 3,000 preferred OP Units, respectively, were redeemed in exchange for cash, and no preferred OP Units were redeemed in exchange for shares of AIR Common Stock or common OP Units. The following table presents a rollforward of the AIR Operating Partnership’s preferred OP Units’ redemption value (in thousands): Balance at January 1, 2023 $ 77,143 Preferred distributions (6,280) Redemption of preferred units and other (3) Net income allocated to preferred units 6,280 Balance at December 31, 2023 $ 77,140 AIR Operating Partnership Partners’ Capital Common Partnership Units The common partnership units held by AIR are classified within Partners’ Capital as General Partner and Special Limited Partner capital and the common OP Units are classified within Limited Partners’ capital in the AIR Operating Partnership’s consolidated balance sheets. The common OP Units are classified within permanent equity as common noncontrolling interests in the AIR Operating Partnership in AIR’s consolidated balance sheets. Common partnership units held by AIR are not redeemable whereas common OP Units are redeemable at the holders’ option, subject to certain restrictions, on the basis of one common OP Unit for either one share of Common Stock or cash equal to the fair value of a share of Common Stock at the time of redemption, in AIR Operating Partnership's sole discretion. AIR has the option to deliver shares of Common Stock in exchange for all or any portion of the common OP Units tendered for redemption. When a limited partner redeems a common OP Unit for Common Stock, Limited Partners’ capital is reduced and the General Partner and Special Limited Partners’ capital is increased. During the years ended December 31, 2023, 2022, and 2021, approximately 528,000, 251,000 and 356,000 common OP Units, respectively, were redeemed in exchange for cash. During the year ended December 31, 2023 no common OP Units were redeemed for shares of Common Stock. During the years ended December 31, 2022 and 2021, approximately 3,000 and 171,000 common OP Units, respectively, were redeemed in exchange for shares of Common Stock.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Share-Based Compensation	Share-Based Compensation We have a stock award and incentive program to attract and retain officers and independent directors. As of December 31, 2023, approximately 2.4 million shares were available for issuance under our Amended and Restated 2020 Stock Award and Incentive Plan (the “Plan”). The total number of shares available for issuance under this Plan may increase due to any forfeiture, cancellation, exchange, surrender, termination, or expiration of an award outstanding under the Plan. Awards under the Plan may be in the form of restricted stock, stock options, or other types of awards as authorized under the Plan. Our plans are administered by the Compensation and Human Resources Committee of the Board of Directors. We grant awards that are subject to time-based vesting and require continuous employment, typically over a period of four years from the grant date. We also grant awards that vest based on AIR's total shareholder return ("TSR") relative to various indices or other performance based metrics. The vesting of TSR awards is based on AIR’s TSR relative to apartment REIT indices, or other real estate indices, over a forward-looking performance period of three years. Earned TSR-based awards, if any, typically vest 50% on each of the third anniversary and fourth anniversary of the grant date, based on continued employment. The vesting of performance awards is conditioned on performance goals achieved in the current year, and typically vest over two to three years. Vested LTIP II units may be converted at the holders’ option to common OP Units for a conversion price over a term of 10 years. Our stock options expire generally 10 years from the date of grant. In the case of stock options, the exercise price of the options granted may not be less than the fair market value of a share of Common Stock at the date of grant. We recognize compensation cost associated with time-based awards ratably over the requisite service periods, which are typically four years. We recognize compensation cost related to the TSR-based awards, which have graded vesting periods, over the requisite service period for each separate vesting tranche of the award, commencing on the grant date. The value of the TSR-based awards takes into consideration the probability that the market condition will be achieved; therefore previously recorded compensation cost is not adjusted in the event that the market condition is not achieved and awards do not vest. Total compensation cost recognized for share-based awards was as follows for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Share-based compensation expense (1) $ 8,874 $ 7,463 $ 7,360 Capitalized share-based compensation (2) 422 503 295 Total share-based compensation (3) $ 9,296 $ 7,966 $ 7,655 (1) Amounts are recorded in general and administrative expenses and property management expenses in our consolidated statements of operations. (2) Amounts are recorded in building and improvements in our consolidated balance sheets. (3) Amounts are recorded in additional paid-in capital and common noncontrolling interests in AIR Operating Partnership in the AIR consolidated balance sheets, and in general partner and special limited partner and limited partners in the AIR Operating Partnership consolidated balance sheets. As of December 31, 2023, total unvested compensation cost not yet recognized was $12.9 million. We expect to recognize this compensation over a weighted-average period of approximately 1.6 years. Stock Options As of December 31, 2023, we had stock options outstanding of 831,297, which had no aggregate intrinsic value and a weighted-average remaining contractual term of 2.2 years. We had 718,961 of stock options exercisable as of December 31, 2023, which had no aggregate intrinsic value and a weighted-average remaining contractual term of 1.8 years. The intrinsic value of a stock option represents the amount by which the current price of the underlying stock exceeds the exercise price of the option. During 2023, we granted stock options with a weighted-average grant date fair value of $11.62.We did not grant any stock options during 2022 and 2021. Restricted Stock Awards As of December 31, 2023, we had 134,615 shares unvested at a weighted-average grant date fair value of $47.78 per share for restricted stock awards that vest over time. As of December 31, 2023, we had 308,327 of shares unvested based on the target performance payout, at a weighted-average grant date fair value of $43.72 per share for performance based restricted stock awards. The aggregate fair value of restricted stock awards that vested during the years ended December 31, 2023, 2022, and 2021 was $1.7 million, $4.3 million, and $3.2 million, respectively. LTIP II Units As of December 31, 2023, we had 3,317,384 of TSR LTIP II units unvested, at a weighted-average grant date fair value of $9.20 per share. Determination of Grant-Date Fair Value of Awards Options are granted with an exercise price at the fair market value of our Common Stock on the date of grant and expiration, subject to employment, which is generally 10 years from the date of grant. Factors considered are the simulated stock price as well as total stockholder return relative to both the NAREIT Equity Apartment Index and the MSCI US REIT Index. We estimated the fair value of TSR-based awards granted in 2023, 2022, and 2021 using a Monte Carlo model with the assumptions set forth in the table below. The risk-free interest rate reflects the annualized yield of a zero coupon United States Treasury security with a term equal to the expected term of the awards. The expected dividend yield reflects expectations regarding cash dividend amounts per share paid on our Common Stock during the expected term of the awards. Expected volatility reflects an average of the historical volatility of our Common Stock during the historical period commensurate with the expected term of the award that ended on the date of grant, and the implied volatility is calculated from observed call option contracts closest to the expected term. The derived vesting period of restricted stock and TSR LTIP I units was determined based on the graded vesting terms. The expected term of the stock options and TSR LTIP II units was based on historical exercises and post-vesting terminations. The valuation assumptions for the 2023, 2022, and 2021 grants were as follows: 2023 2022 2021 Grant date market value of a common share $ 38.26 $ 53.91 $ 36.84 Risk-free interest rate 3.85%- 4.14% 1.20% - 1.68% 0.24% - 0.78% Dividend yield 4.70 % 3.50 % 4.00 % Expected volatility 28.56% - 28.59% 22.63% - 24.83% 23.08% - 28.21% Derived vesting period of TSR Restricted Stock and TSR LTIP I units 3.5 years 3.5 years 3.2 years Weighted average expected term of TSR Stock Options and LTIP II units 5.5 years 5.4 years 5.4 years The grant date fair value for the time-based restricted stock awards reflects the closing price of a share of our Common Stock on the grant date.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes During the year ended December 31, 2020, and consistent with AIR’s simplified business structure and strategy, we converted one of our former taxable REIT subsidiaries into a REIT, and we elected for such entity to be taxed as a REIT under the Code commencing with its taxable year ended December 31, 2021. As a result, AIR has lower income taxes on a consolidated basis, providing more cash for distributions and other corporate uses. As a REIT, this subsidiary will generally be allowed a deduction for dividends that it pays, and therefore, will not be subject to United States federal corporate income tax on the taxable income that is currently distributed to stockholders, however, it may be subject to federal and state tax on the net built-in gain in the converted property under the rules of Section 1374 of the Code, certain state gross income and franchise taxes, as well as taxes on any undistributed income and federal and state corporate taxes on any income earned. The income tax effects of a REIT conversion for financial reporting purposes are reflected in the period in which all significant actions necessary to qualify as a REIT are completed and the entity has committed to becoming a REIT, including (i) obtaining approval from the appropriate parties; (ii) purging through a distribution to stockholders any accumulated earnings and profits from its operations as a C corporation; and (iii) having any remaining actions for the entity to achieve REIT status be perfunctory legal and administrative matters. All significant actions necessary to qualify as a REIT were met as of December 31, 2020, and as such its deferred tax assets and liabilities as of that date were adjusted to reflect a tax rate of zero percent, resulting in the elimination of its deferred tax assets and liabilities as of December 31, 2020. Because the statute of limitations has not yet elapsed, our United States federal income tax returns for the year ended December 31, 2015, and subsequent years and certain of our state income tax returns for the year ended December 31, 2019, and subsequent years are currently subject to examination by the IRS or other taxing authorities. We include any interest and penalties related to income taxes within income tax (expense) benefit in our consolidated statements of operations. Significant components of the income tax benefit or expense are as follows and are classified within income tax (expense) benefit in our consolidated statements of operations for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Current: Federal $ (1,349) $ (756) $ 7,409 State (952) (2,807) (1,971) Total current (2,301) (3,563) 5,438 Deferred: Federal (102) (291) (153) State (24) (69) (39) Total deferred (126) (360) (192) Total (expense) benefit $ (2,427) $ (3,923) $ 5,246 Consolidated income or loss subject to tax consists of pretax income or loss from the continuing operations of our TRS entities and income and gains retained by the continuing operations of the REIT. For the years ended December 31, 2023, 2022, and 2021, we had consolidated net income subject to tax of $24.1 million, $7.4 million, $28.9 million, respectively. The reconciliation of income tax computed at the United States statutory rate to income tax benefit is shown below (dollars in thousands): 2023 2022 2021 Amount Percent Amount Percent Amount Percent Tax expense provision at United States statutory rates on consolidated income from continuing operations subject to tax $ (5,065) (21.0 %) $ (1,554) (21.0 %) $ (6,064) (21.0 %) State income tax expense, net of federal tax expense (996) (4.1 %) (2,853) (38.6 %) (2,011) (7.0 %) Tax credits 3,420 14.2 % 191 2.6 % 3,508 12.1 % TRS REIT election — — % — — % 9,656 33.4 % Other 214 0.9 % 293 4.0 % 157 0.5 % Total income tax expense $ (2,427) (10.0 %) $ (3,923) (53.0 %) $ 5,246 18.0 % For income tax purposes, dividends paid to holders of Common Stock primarily consist of ordinary income, capital gains, qualified dividends, unrecaptured Section 1250 gains, return of capital, or a combination thereof. For the years ended December 31, 2023, 2022, and 2021, dividends per share held for the entire year were estimated to have the following tax attributes: 2023 2022 2021 (unaudited) Amount Percentage Amount Percentage Amount Percentage Ordinary income $ 0.24 13.1 % $ 0.21 11.8 % $ — — % Capital gains 0.06 3.5 % 1.37 76.0 % 0.44 25.3 % Qualified dividends — — % 0.03 1.9 % — —% Unrecaptured Section 1250 gain — — % 0.19 10.3 % 0.13 7.5 % Return of capital 1.50 83.4 % — — % 1.17 67.2 % Total $ 1.80 100.0 % $ 1.80 100.0 % $ 1.74 100.0 %

Earnings and Dividends per Shar

Earnings and Dividends per Share and per Unit	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Earnings and Dividends per Share and per Unit	Earnings and Dividends per Share and per Unit AIR and the AIR Operating Partnership calculate basic earnings per common share and basic earnings per common unit, respectively, based on the weighted-average number of shares of Common Stock and common partnership units outstanding, respectively. We calculate diluted earnings per share and diluted earnings per unit taking into consideration dilutive Common Stock and common partnership unit equivalents and dilutive convertible securities outstanding during the period. Our Common Stock and common partnership unit equivalents include: (i) options to purchase shares of Common Stock, which, if exercised, would result in AIR’s issuance of additional shares and the AIR Operating Partnership’s issuance to AIR of additional common partnership units equal to the number of shares purchased under the options; (ii) unvested total stockholder return (“TSR”) restricted stock awards that do not meet the definition of participating securities, which would result in an increase in the number of shares of Common Stock and common partnership units outstanding equal to the number of the shares that vest; and (iii) preferred OP Units, which may be redeemed at the holders’ option for cash or shares of Common Stock. Common partnership unit equivalents also include unvested long-term incentive partnership units. We include in the denominator securities with dilutive effect in calculating diluted earnings (loss) per share and per unit during these periods. Our restricted stock awards that are subject to time-based vesting receive non-forfeitable dividends similar to shares of Common Stock and common partnership units prior to vesting. Our TSR long-term incentive partnership units receive non-forfeitable distributions based on specified percentages of the distributions paid to common partnership units prior to vesting and conversion. The unvested restricted shares and units related to these awards are participating securities. We include the effect of participating securities in basic and diluted earnings per share and unit computations using the two-class method of allocating distributed and undistributed earnings when the two-class method is more dilutive than the treasury stock method. Reconciliations of the numerator and denominator in the calculations of basic and diluted earnings per share and per unit for the years ended December 31, 2023, 2022, and 2021 are as follows (in thousands, except per share and per unit data): 2023 2022 2021 Earnings per share Numerator: Basic and dilutive net income attributable to AIR common stockholders $ 634,444 $ 903,642 $ 447,124 Effect of dilutive instruments 6,280 6,388 — Dilutive net income attributable to AIR common stockholders $ 640,724 $ 910,030 $ 447,124 Denominator – shares: Basic weighted-average common shares outstanding 147,899 154,093 154,135 Dilutive common share equivalents outstanding 2,321 2,494 368 Dilutive weighted-average common shares outstanding 150,220 156,587 154,503 Earnings per share – basic $ 4.29 $ 5.86 $ 2.90 Earnings per share – diluted $ 4.27 $ 5.81 $ 2.89 Earnings per unit Numerator: Basic and dilutive net income attributable to the AIR Operating Partnership’s common unitholders $ 677,165 $ 962,414 $ 475,557 Effect of dilutive instruments 6,280 6,388 — Basic and dilutive net income attributable to the AIR Operating Partnership’s common unitholders $ 683,445 $ 968,802 $ 475,557 Denominator – units: Basic weighted-average common units outstanding 157,687 164,141 162,739 Dilutive common unit equivalents outstanding 2,321 2,494 369 Dilutive weighted-average common units outstanding 160,008 166,635 163,108 Earnings per unit – basic $ 4.29 $ 5.86 $ 2.92 Earnings per unit – diluted $ 4.27 $ 5.81 $ 2.92 The number of common share equivalent securities excluded from the diluted earnings per share calculation were approximately 3.4 million, —, and 1.5 million for the years ended December 31, 2023, 2022, and 2021 respectively.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We estimate the fair value of certain assets and liabilities using pricing models that rely on observable market information, including contractual terms, market prices, and interest rate yield curves. A three-level valuation hierarchy prioritizes observable and unobservable inputs used to measure fair value, as described below: • Level 1 – Quoted prices in active markets for identical assets or liabilities that the entity has the ability to access. • Level 2 – Observable inputs other than prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated with observable market data. • Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies, and similar techniques that use significant unobservable inputs. Recurring Fair Value Measurements The following table summarizes investments measured at fair value on a recurring basis, which are presented in other assets, net, and accrued liabilities and other in our consolidated balance sheets (in thousands): As of December 31, 2023 As of December 31, 2022 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Interest rate option (1) $ — $ — $ — $ — $ 53,481 $ — $ 53,481 $ — Interest rate swaps - pay-fixed, receive floating $ 14,679 $ — $ 14,679 $ — $ 32,222 $ — $ 32,222 $ — Interest rate swaps - pay-floating, receive fixed $ 465 $ — $ 465 $ — $ — $ — $ — $ — Interest rate swap - forward starting $ 331 $ — $ 331 $ — $ — $ — $ — $ — Treasury rate locks $ — $ — $ — $ — $ 319 $ — $ 319 $ — (1) During the second quarter of 2023, the interest rate swap option asset and offsetting liability associated with the Parkmerced mezzanine investment was settled, resulting in equal decreases in other assets and accrued liabilities and other in the consolidated balance sheets which represents non-cash activity. Financial Assets and Liabilities Not Measured at Fair Value We believe that the carrying value of the consolidated amounts of cash and cash equivalents, restricted cash, accounts receivable, and accounts payable approximated their estimated fair value as of December 31, 2023 and 2022, due to their relatively short-term nature and high probability of realization. The carrying value of our revolving credit facility and term loans, which we classify as Level 2 in the GAAP fair value hierarchy, approximated their estimated fair value as of December 31, 2023 and 2022, as they bear interest at floating rates which approximate market rates. We classify the fair value of our non-recourse property debt, unsecured notes payable, seller financing notes receivable, and preferred equity investment within Level 2 of the GAAP fair value hierarchy, as summarized in the following table (in thousands): As of December 31, 2023 As of December 31, 2022 Carrying Value Fair Value Carrying Value Fair Value Non-recourse property debt $ 2,236,975 $ 2,001,532 $ 1,994,651 $ 1,753,222 Unsecured notes payable $ 400,000 $ 384,244 $ 400,000 $ 371,368 Seller financing note receivable, net (1) $ 32,459 $ 33,042 $ 31,611 $ 32,286 Preferred equity investment (2) $ 22,693 $ 23,562 $ — $ —

Derivative Financial Instrument

Derivative Financial Instruments and Hedging Activities	12 Months Ended
	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments and Hedging Activities	Derivative Financial Instruments and Hedging Activities Risk Management Objective of Using Derivatives Our objectives in using interest rate derivatives are to add predictability to interest expense and to manage our exposure to interest rate movements. To accomplish these objectives, we primarily use interest rate swaps and treasury locks as part of our interest rate management strategy. Interest rate swaps primarily involve the receipt of variable-rate or fixed-rate amounts from a counterparty in exchange for us making fixed-rate or variable-rate payments over the life of the agreements without exchange of the underlying notional amounts. Changes in fair value of derivatives designated as cash flow hedges are recognized in accumulated other comprehensive income and subsequently reclassified into earnings as an increase or decrease to interest expense. During the year ended December 31, 2023, we reclassified gains of $25.8 million out of accumulated other comprehensive income into interest expense, inclusive of the Company's acceleration of the reclassification of amounts in accumulated other comprehensive income given that certain hedged forecasted transactions are not expected to occur. During the third quarter of 2023, the Company accelerated a gain of $11.5 million into earnings due to the early payoff of the hedged term loans previously designated. During the year ended December 31, 2022, we reclassified losses of $0.3 million out of accumulated other comprehensive income into interest expense. As of December 31, 2023, we estimate that during the next 12 months, we will reclassify into earnings approximately $6.7 million of the unrealized gain in accumulated other comprehensive income. Changes in fair value of derivatives not designated in a hedge relationship, or economic hedges, are recognized in gain on derivative instruments, net, in our consolidated statements of operations. During the year ended December 31, 2023, we recorded gains of $16.7 million. During the year ended December 31, 2022, no amounts were recognized related to derivatives not designated in a hedge relationship. During the second quarter of 2023, we de-designated $830 million of notional value pay-fixed, receive-floating interest rate swaps. As a result, the accumulated unrealized gains at time of de-designation of $29.5 million was expected to be reclassified into earnings over the remaining term of the forecasted transactions. During the year ended December 31, 2023, $4.2 million of this balance was reclassified out of accumulated other comprehensive income into interest expense, and $11.5 million was accelerated into interest expense. The remaining balance of $13.8 million is included within accumulated other comprehensive income as of December 31, 2023 and will be reclassified into earnings over the remaining term of the forecasted transaction. During the year ended December 31, 2023, we fully terminated eight and partially terminated two interest rate swap positions not designated as hedging instruments. Four of the fully terminated instruments and one of the partially terminated instruments were pay-floating, receive-fixed interest rate swaps with a notional value of $330 million and $100 million, respectively. Four of the fully terminated and one of the partially terminated instruments were offsetting pay-fixed, receive-floating interest rate swaps with a notional value of $330 million, and $100 million, respectively. Upon termination, AIR received $15.5 million in cash. During the fourth quarter of 2023, AIR entered into a notional value $125 million pay-fixed, receive-floating interest rate swap, economically hedging the remaining $125 million of variable-rate term loans, which results in the outstanding term loan balance of $475 million, with an effective interest rate of 4.3%. As of December 31, 2023, AIR had a notional value of $555 million of pay-fixed, receive-floating interest rate swaps that are not designated as hedging instruments, and a notional value of $50 million of forward starting interest rate swaps that are not designated as hedging instruments. These derivative instruments are partially offset by a notional value of $80 million of pay-floating, receive-fixed interest rate swaps that are not designated as hedging instruments. Accordingly, the changes in the fair value of these derivatives are recognized in gain on derivative instruments, net, in our consolidated statements of operations. As a result of the $80 million of pay-floating, receive-fixed interest rate swaps that are not designated as hedging instruments, we expect to receive monthly fixed interest income representing the spread between the offsetting pay-fixed and receive-fixed legs of our interest rate swap positions over a weighted-average term of 2.8 years. The following table summarizes our derivative financial instruments (dollars in thousands): As of December 31, 2023 Number of Aggregate Notional Derivative Assets Derivative Liabilities Instruments Amount Fair Value Derivatives not designated as hedging instruments: Interest rate swaps - pay-fixed, receive floating 7 $ 555,000 $ 15,266 $ (587) Interest rate swaps - pay-floating, receive fixed 2 $ 80,000 $ 472 $ (7) Interest rate swap, forward starting 1 $ 50,000 $ 331 $ — As of December 31, 2022 Number of Aggregate Notional Derivative Assets Derivative Liabilities Instruments Amount Fair Value Derivatives designated as hedging instruments: Treasury rate lock 1 $ 100,000 $ 319 $ — Interest rate swaps - pay-fixed, receive floating 10 $ 830,000 $ 32,222 $ —

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Variable Interest Entities Consolidated Entities AIR consolidates the AIR Operating Partnership, a VIE of which AIR is the primary beneficiary. AIR, through the AIR Operating Partnership, consolidates all VIEs for which it is the primary beneficiary. Substantially all of the assets and liabilities of AIR are that of the AIR Operating Partnership. The AIR Operating Partnership consolidates (i) three VIEs that own interests in one or more apartment communities and are typically structured to generate a return for their partners through the operation and ultimate sale of the communities and (ii) one VIE related to a lessor entity that owns an interest in a property leased to a third party. The AIR Operating Partnership is the primary beneficiary in the limited partnerships in which it is the sole decision maker and has a substantial economic interest. The table below summarizes apartment community information regarding VIEs consolidated by the AIR Operating Partnership: December 31, 2023 (1) December 31, 2022 VIEs with interests in apartment communities 3 5 Apartment communities owned by VIEs 14 16 Apartment homes in communities owned by VIEs 4,866 5,369 (1) During 2023, the number of our VIEs with interests in apartment communities decreased due to our Core JV partner's acquisition of an indirect 47% interest through the Core JV in one consolidated limited partnership with 175 apartment homes, and our purchase of the remaining non-controlling interest in a consolidated limited partnership with 328 apartment homes, which was subsequently contributed to the Core JV during the third quarter of 2023. Assets of the AIR Operating Partnership’s consolidated VIEs must first be used to settle the liabilities of such consolidated VIEs. These consolidated VIEs’ creditors do not have recourse to the general credit of the AIR Operating Partnership. Assets and liabilities of VIEs, excluding those of the AIR Operating Partnership, are summarized in the table below (in thousands): December 31, 2023 December 31, 2022 ASSETS: Net real estate $ 1,013,770 $ 1,066,482 Cash and cash equivalents 41,219 54,319 Restricted cash 2,179 2,378 Other assets, net 22,546 20,944 LIABILITIES: Non-recourse property debt, net $ 1,196,280 $ 1,212,065 Accrued liabilities and other 34,903 35,365 Unconsolidated Entities We have an interest in a partnership that owns Parkmerced Apartments, which meets the definition of a VIE. However, we are not the primary beneficiary and do not consolidate this partnership. Subsequent to 2020, all risks and rewards of ownership are Aimco’s, however, as legal transfer has not occurred, there is an equal and offsetting liability included in accrued liabilities and other in our consolidated balance sheets. Accordingly, there is no net effect on AIR’s equity or the AIR Operating Partnership’s partners’ capital, and any changes in the equal and offsetting asset and liability represent non-cash activity. As of December 31, 2023 and 2022, the investment balance of $— and $158.7 million, respectively, is included in other assets, net in our consolidated balance sheets. Please see Note 6 for further discussion regarding our unconsolidated joint ventures.

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Business Segments	Business Segments We have two segments: Same Store and Other Real Estate. Our Same Store segment includes communities that are owned and managed by AIR and have reached a stabilized level of operations. Our Other Real Estate segment includes four properties acquired in 2022, four properties previously leased to Aimco, and four properties acquired in 2023. Our CODM uses proportionate property NOI to assess the operating performance of our communities. Proportionate property NOI reflects our share of rental and other property revenues, excluding utility reimbursements, less direct property operating expenses, net of utility reimbursements. In our consolidated statements of operations, utility reimbursements are included in rental and other property revenues in accordance with GAAP. As of December 31, 2023, our Same Store segment included 63 apartment communities with 22,794 apartment homes and our Other Real Estate segment included 12 apartment communities with 3,832 apartment homes. The following tables present the total revenues, property operating expenses, proportionate property net operating income (loss), and income before income tax expense of our segments on a proportionate basis, excluding amounts related to communities sold. To reflect how the CODM evaluates the business, prior period segment information has been recast to conform with our reportable segment composition as of December 31, 2023 (in thousands): Same Other Proportionate Corporate and Consolidated Year ended December 31, 2023: Total revenues $ 600,142 $ 119,587 $ 85,825 $ 14,482 $ 820,036 Property management and operating expenses 152,898 37,899 44,295 40,740 275,832 Other operating expenses not allocated to segments (3) — — — 393,976 393,976 Total operating expenses 152,898 37,899 44,295 434,716 669,808 Proportionate property net operating income (loss) 447,244 81,688 41,530 (420,234) 150,228 Other items included in income before income tax expense (4) — — — 541,486 541,486 Income before income tax expense $ 447,244 $ 81,688 $ 41,530 $ 121,252 $ 691,714 Same Other Proportionate Corporate and Consolidated Year ended December 31, 2022: Total revenues $ 556,318 $ 37,783 $ 125,800 $ 53,822 $ 773,723 Property management and operating expenses 147,084 12,399 51,350 50,431 261,264 Other operating expenses not allocated to segments (3) — — — 384,957 384,957 Total operating expenses 147,084 12,399 51,350 435,388 646,221 Proportionate property net operating income (loss) 409,234 25,384 74,450 (381,566) 127,502 Other items included in income before income tax expense (4) — — — 846,471 846,471 Income before income tax expense $ 409,234 $ 25,384 $ 74,450 $ 464,905 $ 973,973 Same Other Proportionate Corporate and Consolidated Year ended December 31, 2021: Total revenues $ 499,896 $ — $ 113,634 $ 127,323 $ 740,853 Property management and operating expenses 140,829 — 48,101 79,171 268,101 Other operating expenses not allocated to segments (3) — — — 365,547 365,547 Total operating expenses 140,829 — 48,101 444,718 633,648 Proportionate property net operating income (loss) 359,067 — 65,533 (317,395) 107,205 Other items included in income before income tax expense (4) — — — 366,773 366,773 Income before income tax expense $ 359,067 $ — $ 65,533 $ 49,378 $ 473,978 (1) Represents adjustments to: (i) exclude AIR’s proportionate share of the results of unconsolidated apartment communities, which is excluded in the related consolidated amounts, and (ii) include the noncontrolling interests in consolidated real estate partnerships’ proportionate share of the results of communities, which is included in the related consolidated amounts. Also includes the reclassification of utility reimbursements from revenues to property operating expenses for the purpose of evaluating segment results. Utility reimbursements are included in rental and other property revenues in our consolidated statements of operations prepared in accordance with GAAP. (2) Includes: (i) the operating results of apartment communities sold during the periods shown or held for sale at the end of the period, if any, (ii) property management revenues, which are not part of our segment performance measure, property management expenses and casualty gains and losses, which are included in consolidated property management and operating expenses and are not part of our segment performance measure, and (iii) the depreciation of capitalized costs of non-real estate assets. (3) Includes depreciation and amortization, general and administrative expenses, and other expenses, net, and may also include write-offs of deferred leasing commissions, which are not included in our measure of segment performance. (4) Includes interest income, interest expense, loss on extinguishment of debt, gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties, loss from unconsolidated real estate partnerships, and gain on derivative instruments, net. The assets of our segments and the consolidated assets not allocated to our segments were as follows (in thousands): December 31, 2023 December 31, 2022 Same Store $ 4,131,039 $ 4,610,356 Other Real Estate 1,519,326 1,211,136 Corporate and other assets (1) 484,387 730,391 Total consolidated assets $ 6,134,752 $ 6,551,883 (1) Includes the assets not allocated to our segments including: (i) corporate assets; (ii) the mezzanine loan investment where the rights and obligations of ownership have been assigned to Aimco; and (iii) properties sold or classified as held for sale. Capital additions related to our segments were as follows (in thousands): 2023 2022 2021 Same Store $ 134,850 $ 145,881 $ 130,207 Other Real Estate 20,724 3,825 — Total capital additions $ 155,574 $ 149,706 $ 130,207

Schedule III_ Real Estate and A

Schedule III: Real Estate and Accumulated Depreciation	12 Months Ended
	Dec. 31, 2023
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation Disclosure [Abstract]
Schedule III: Real Estate and Accumulated Depreciation	APARTMENT INCOME REIT CORP. APARTMENT INCOME REIT, L.P. SCHEDULE III: REAL ESTATE AND ACCUMULATED DEPRECIATION December 31, 2023 (In Thousands, Except Apartment Home Data) Apartment Community Name Apartment (1) Location Year Apartment Initial Cost (2) As of December 31, 2023 Land Buildings and Land Buildings and (3) (4) Accumulated Depreciation (AD) Total Cost (5) Same Store: 21 Fitzsimons Mid Rise Aug 2014 Aurora, CO 2008 601 $ 13,176 $ 110,795 $ 40,086 $ 13,176 $ 150,881 $ 164,057 $ (53,485) $ 110,572 $ 81,838 3400 Avenue of the Arts Mid Rise Mar 2002 Costa Mesa, CA 1987 770 57,241 65,506 101,943 57,241 167,449 224,690 (116,299) 108,391 — 777 South Broad Street Mid Rise May 2018 Philadelphia, PA 2010 146 6,986 67,512 5,229 6,986 72,741 79,727 (16,149) 63,578 37,051 Axiom Mid Rise Apr 2015 Cambridge, MA 2015 115 — 63,612 5,133 — 68,745 68,745 (21,542) 47,203 — Bay Parc Plaza High Rise Sep 2004 Miami, FL 2000 474 22,680 41,847 65,092 22,680 106,939 129,619 (43,586) 86,033 69,987 Boulder Creek Garden Jul 1994 Boulder, CO 1973 221 754 7,730 19,634 754 27,364 28,118 (21,125) 6,993 — Broadcast Center Garden Mar 2002 Los Angeles, CA 1990 279 29,407 41,244 44,820 29,407 86,064 115,471 (46,287) 69,184 — Calhoun Beach Club High Rise Dec 1998 Minneapolis, MN 1928 332 11,708 73,334 62,140 11,708 135,474 147,182 (101,407) 45,775 — Charlesbank Apartment Homes Mid Rise Sep 2013 Watertown, MA 2012 44 3,399 11,726 1,720 3,399 13,446 16,845 (4,902) 11,943 — Chestnut Hall High Rise Oct 2006 Philadelphia, PA 1923 315 12,338 14,299 14,895 12,338 29,194 41,532 (16,044) 25,488 32,291 City Center on 7th Garden Jun 2021 Pembroke Pines, FL 2014 700 35,196 186,823 33,250 35,196 220,073 255,269 (21,858) 233,411 — Flamingo Point, Center Tower High Rise Sep 1997 Miami Beach, FL 2003 513 15,279 29,358 240,993 15,279 270,351 285,630 (146,577) 139,053 — Flamingo Point, South Tower (6) High Rise Sep 1997 Miami Beach, FL 1960 260 — 14,570 74,656 — 89,226 89,226 (21,537) 67,689 — Foxchase Garden Dec 1997 Alexandria, VA 1940 2,113 15,496 96,062 95,399 15,496 191,461 206,957 (127,305) 79,652 170,000 Hidden Cove Garden Jul 1998 Escondido, CA 1983 334 3,043 17,616 20,372 3,043 37,988 41,031 (23,334) 17,697 64,757 Hidden Cove II Garden Jul 2007 Escondido, CA 1986 118 12,849 6,530 7,518 12,849 14,048 26,897 (7,867) 19,030 25,183 Hillcreste Garden Mar 2002 Century City, CA 1989 315 35,862 47,216 26,720 35,862 73,936 109,798 (41,057) 68,741 — Indian Oaks Garden Mar 2002 Simi Valley, CA 1986 254 24,523 15,801 13,395 24,523 29,196 53,719 (21,548) 32,171 58,955 Indigo High Rise Aug 2016 Redwood City, CA 2016 463 26,932 296,116 12,194 26,932 308,310 335,242 (80,869) 254,373 171,938 Laurel Crossing Garden Jan 2006 San Mateo, CA 1971 418 49,474 17,756 20,756 49,474 38,512 87,986 (22,212) 65,774 — Lincoln Place (7) Garden Oct 2004 Venice, CA 1951 795 128,332 10,439 256,641 44,198 351,214 395,412 (193,540) 201,872 169,960 Malibu Canyon Garden Mar 2002 Calabasas, CA 1986 698 69,834 53,438 45,720 69,834 99,158 168,992 (70,914) 98,078 158,950 Mariners Cove Garden Mar 2002 San Diego, CA 1984 500 — 66,861 18,641 — 85,502 85,502 (52,801) 32,701 — Meadow Creek Garden Jul 1994 Boulder, CO 1968 332 1,435 24,533 13,660 1,435 38,193 39,628 (27,091) 12,537 — Mezzo High Rise Mar 2015 Atlanta, GA 2008 95 4,292 34,178 3,616 4,292 37,794 42,086 (12,332) 29,754 — Monterey Grove Garden Jun 2008 San Jose, CA 1999 224 34,325 21,939 19,497 34,325 41,436 75,761 (20,533) 55,228 45,541 North Park High Rise Oct 2021 Chevy Chase, MD 1973 310 42,900 68,090 11,492 42,933 79,549 122,482 (6,726) 115,756 73,634 Apartment Community Name Apartment (1) Location Year Apartment Initial Cost (2) As of December 31, 2023 Land Buildings and Land Buildings and (3) (4) Accumulated Depreciation (AD) Total Cost (5) Ocean House on Prospect Mid Rise Apr 2013 La Jolla, CA 1970 53 12,528 $ 18,805 $ 17,298 $ 12,528 $ 36,103 $ 48,631 $ (15,618) $ 33,013 $ — One Ardmore Mid Rise Apr 2019 Ardmore, PA 2019 110 4,929 61,631 4,135 4,929 65,766 70,695 (11,520) 59,175 28,504 One Canal High Rise Sep 2013 Boston, MA 2016 310 — 15,873 184,077 — 199,950 199,950 (59,287) 140,663 — Pacific Bay Vistas (7) Garden Mar 2001 San Bruno, CA 1987 308 28,694 62,460 34,167 23,354 101,967 125,321 (51,306) 74,015 95,804 Pacifica Park Garden Jul 2006 Pacifica, CA 1977 104 12,970 6,579 9,765 12,970 16,344 29,314 (10,197) 19,117 37,264 Palazzo at Park La Brea, The Mid Rise Feb 2004 Los Angeles, CA 2002 521 48,362 125,464 61,144 48,362 186,608 234,970 (111,787) 123,183 205,883 Palazzo East at Park La Brea, The Mid Rise Mar 2005 Los Angeles, CA 2005 611 72,578 136,503 43,699 72,578 180,202 252,780 (110,240) 142,540 174,531 Parc Mosaic Garden Dec 2014 Boulder, CO 1970 226 15,300 — 111,319 15,300 111,319 126,619 (24,893) 101,726 — Peachtree Park Garden Jan 1996 Atlanta, GA 1969 303 4,684 11,713 17,696 4,684 29,409 34,093 (20,455) 13,638 — Preserve at Marin Mid Rise Aug 2011 Corte Madera, CA 1964 126 13,516 30,132 81,922 13,516 112,054 125,570 (48,841) 76,729 — Residences at Capital Crescent Trail High Rise Oct 2021 Bethesda, MD 2002 258 15,975 84,167 8,019 15,975 92,186 108,161 (7,664) 100,497 — Royal Crest Estates Garden Aug 2002 North Andover, MA 1970 588 51,292 36,808 29,995 51,292 66,803 118,095 (45,758) 72,337 — Saybrook Pointe Garden Dec 2014 San Jose, CA 1995 324 32,842 84,457 27,878 32,842 112,335 145,177 (37,931) 107,246 107,347 SouthStar Lofts High Rise May 2018 Philadelphia, PA 2014 85 1,780 37,428 1,458 1,780 38,886 40,666 (8,261) 32,405 17,000 Sterling Apartment Homes, The Garden Oct 1999 Philadelphia, PA 1961 534 8,871 55,365 120,985 8,871 176,350 185,221 (121,690) 63,531 — The Left Bank Mid Rise May 2018 Philadelphia, PA 1929 282 — 130,893 26,672 — 157,565 157,565 (34,431) 123,134 73,658 Tremont Mid Rise Dec 2014 Atlanta, GA 2009 78 5,274 18,011 4,365 5,274 22,376 27,650 (7,708) 19,942 — Vaughan Place Apartments (6) High Rise Oct 2021 Washington, D.C. 1988 382 47,276 125,213 17,339 47,244 142,584 189,828 (12,428) 177,400 150,000 Villas at Park La Brea, The Garden Mar 2002 Los Angeles, CA 2002 250 8,630 48,871 24,942 8,630 73,813 82,443 (46,528) 35,915 — Villas of Pasadena Mid Rise Jan 2006 Pasadena, CA 1973 92 9,693 6,818 5,826 9,693 12,644 22,337 (7,888) 14,449 20,500 Vivo High Rise Jun 2016 Cambridge, MA 2015 91 6,450 35,974 6,623 6,450 42,597 49,047 (19,812) 29,235 — Waterways Village Garden Jun 1997 Aventura, FL 1994 180 4,504 11,064 19,088 4,504 30,152 34,656 (19,909) 14,747 — Total Same Store 17,555 $ 1,063,609 $ 2,649,160 $ 2,133,624 $ 974,136 $ 4,872,257 $ 5,846,393 $ (2,173,079) $ 3,673,314 $ 2,070,576 Other Real Estate: 707 Leahy Garden Sep 2022 Redwood City, CA 1973 110 $ 20,956 $ 62,605 $ 185 $ 20,956 $ 62,790 $ 83,746 $ (3,069) $ 80,677 $ — Brizo Apartments Garden Jul 2023 Durham, NC 2019 260 7,652 60,170 1,055 7,652 61,225 68,877 (738) 68,139 41,026 Flamingo Point, North Tower High Rise Sep 2022 Miami Beach, FL 1960 366 91,529 290,682 1,561 91,529 292,243 383,772 (13,602) 370,170 — PRISM Mid Rise Sep 2022 Cambridge, MA 2019 136 13,768 74,541 572 13,768 75,113 88,881 (3,668) 85,213 — Southgate Towers High Rise Jan 2023 Miami Beach, FL 1958 495 99,338 187,427 3,392 99,338 190,819 290,157 (6,855) 283,302 84,336 The District at Flagler Village High Rise Jul 2022 Fort Lauderdale, FL 2021 350 14,472 156,718 1,526 14,472 158,244 172,716 (8,721) 163,995 — The Fremont Mid Rise Sep 2022 Aurora, CO 2020 253 7,218 92,621 213 7,218 92,834 100,052 (4,651) 95,401 — Apartment Community Name Apartment (1) Location Year Apartment Initial Cost (2) As of December 31, 2023 Land Buildings and Land Buildings and (3) (4) Accumulated Depreciation (AD) Total Cost (5) The Reserve at Coconut Point Garden May 2022 Fort Myers, FL 2022 180 $ 5,162 $ 66,593 $ 237 $ 5,162 $ 66,830 $ 71,992 $ (4,732) $ 67,260 $ — Villages at Olde Towne Garden Jul 2023 Raleigh, NC 2022 360 11,575 70,767 535 11,575 71,302 82,877 (1,244) 81,633 33,500 Watermarc at Biscayne Bay High Rise Jun 2022 Miami, FL 2021 296 34,710 174,237 2,531 34,710 176,768 211,478 (10,271) 201,207 — Willard Towers High Rise Jun 2022 Washington, D.C. 1969 525 334 179,141 12,701 334 191,842 192,176 (10,776) 181,400 — Other (8) 4,863 — 12,590 4,860 12,590 17,450 (4,183) 13,267 7,537 Total Other Real Estate 3,331 $ 311,577 $ 1,415,502 $ 37,098 $ 311,574 $ 1,452,600 $ 1,764,174 $ (72,510) $ 1,691,664 $ 166,399 Total Portfolio 20,886 $ 1,375,186 $ 4,064,662 $ 2,170,722 $ 1,285,710 $ 6,324,857 $ 7,610,567 $ (2,245,589) $ 5,364,978 $ 2,236,975 (1) Date we acquired the apartment community or first consolidated the partnership that owns the community. (2) Includes costs capitalized since acquisition or date of initial consolidation of the community. (3) The aggregate cost of land and depreciable property for federal income tax purposes was approximately $6.9 billion as of December 31, 2023 (unaudited). (4) Depreciable life for buildings and improvements ranges from 5 to 30 years and is calculated on a straight-line basis. (5) Encumbrances are presented before reduction for debt issuance costs. (6) Initial cost of buildings and improvements includes the cost of additional apartment homes acquired subsequent to consolidation. (7) The current carrying value of the apartment community reflects an impairment loss recognized. (8) Other includes apartment communities under development, land parcels, and certain non-residential properties held for future development. APARTMENT INCOME REIT CORP. APARTMENT INCOME REIT, L.P. SCHEDULE III: REAL ESTATE AND ACCUMULATED DEPRECIATION For the Years Ended December 31, 2023, 2022, and 2021 (In Thousands) 2023 2022 2021 Total real estate balance at beginning of year $ 8,076,394 $ 6,885,081 $ 7,468,864 Additions during the year: Acquisitions and lease cancellation 447,945 1,300,122 723,599 Capital additions 168,248 193,360 168,920 Amounts related to assets held for sale — — (253,547) Dispositions and other (1,082,020) (302,169) (1,222,755) Total real estate balance at end of year $ 7,610,567 $ 8,076,394 $ 6,885,081 Accumulated depreciation balance at beginning of year $ 2,449,883 $ 2,284,793 $ 2,455,505 Depreciation 310,952 308,382 298,789 Amounts related to assets held for sale — — (107,055) Dispositions and other (515,246) (143,292) (362,446) Accumulated depreciation balance at end of year $ 2,245,589 $ 2,449,883 $ 2,284,793

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation	Principles of Consolidation We consolidate variable interest entities (“VIE”), in which we are considered the primary beneficiary. The primary beneficiary is the entity that has (i) the power to direct the activities that most significantly impact the entity’s economic performance, and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could be significant to the VIE. As of December 31, 2023 and 2022, AIR consolidated five and seven VIEs, respectively, including the AIR Operating Partnership. Please see Note 15 for further discussion regarding our consolidated VIEs.
Real Estate	Real Estate Acquisitions Upon the acquisition of real estate, we determine whether the purchase qualifies as an asset acquisition or meets the definition of an acquisition of a business. We generally recognize the acquisition of apartment communities or interests in partnerships that own communities at our cost, including the related transaction costs, as asset acquisitions. We allocate the cost of apartment communities acquired based on the relative fair value of the assets acquired and liabilities assumed. The fair value of these assets and liabilities is determined using valuation techniques that rely on Level 2 and Level 3 inputs within the fair value framework. We determine the fair value of tangible assets, such as land, buildings, furniture, fixtures, and equipment using valuation techniques that consider comparable market transactions, replacement costs, and other available information. We determine the fair value of identified intangible assets or liabilities, which typically relate to in-place leases, using valuation techniques that consider the terms of the in-place leases, current market data for comparable leases, and our experience in leasing similar communities. The intangible assets or liabilities related to in-place leases are comprised of: (a) the value of the above- and below-market leases in-place, measured over the period, including probable lease renewals for below-market leases, that the leases are expected to remain in effect; (b) the estimated unamortized portion of avoided leasing commissions and other costs that ordinarily would be incurred to originate the in-place leases; and (c) the value associated with leased apartment homes during an estimated absorption period, which estimates rental revenue that would not have been earned had leased apartment homes been vacant at the time of acquisition, assuming lease-up periods based on market demand and stabilized occupancy levels. The above- and below-market lease intangibles are amortized to rental revenue over the expected remaining terms of the associated leases, which include reasonably assured renewal periods. Other intangible assets related to in-place leases are amortized to depreciation and amortization over the expected remaining terms of the associated leases. Capital Additions We capitalize costs, including certain indirect costs, incurred in connection with our capital additions activities, including tangible apartment community improvements and replacements of existing apartment community components. Costs, including ordinary repairs, maintenance, and resident turnover costs, are charged to property operating expense as incurred. For the years ended December 31, 2023, 2022, and 2021, we capitalized to buildings and improvements $1.1 million, $1.5 million, and $2.4 million of interest costs, respectively, and $16.2 million, $16.6 million, and $10.3 million of other direct and indirect costs, respectively. Dispositions A property is classified as held for sale when all of the following criteria for a plan of sale have been met: (i) management, having the authority to approve the action, commits to a plan to sell the asset or disposal group; (ii) the asset or disposal group is available for immediate sale in its present condition, subject only to terms that are usual and customary; (iii) an active program to locate a buyer and other actions required to complete the plan to sell the asset or disposal group have been initiated; (iv) the sale of the asset or disposal group is probable and is expected to be completed within one year; (v) the asset or disposal group is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and (vi) actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn, which is typically indicated by receipt of all non-refundable deposits from the buyer pursuant to a sales contract. Depreciation of assets ceases upon designation of a property as held for sale. For sales of real estate, we evaluate whether the disposition represents a strategic shift that has, or will have, a major effect on our operations and financial results. If so, it is classified as discontinued operations in our consolidated financial statements for all periods presented. If not, it is presented in continuing operations in our consolidated financial statements. The disposal of an individual property generally will not represent a strategic shift that has a major effect, and therefore will typically not meet the criteria for classification as a discontinued operations. Gain or loss on real estate dispositions are recognized when we no longer hold a controlling financial interest in the real estate and sufficient consideration has been received. Upon disposition, the related assets and liabilities are derecognized, and the gain or loss on disposition is recognized as the difference between the carrying amount of those assets and liabilities and the value of consideration received. Impairment Real estate and other long-lived assets to be held and used are individually evaluated for impairment when conditions exist that may indicate the carrying amount of a long-lived asset may not be recoverable. We use the held for sale impairment model for properties classified as held for sale, whereby an impairment charge is recognized if the carrying amount of the long-lived asset classified as held for sale exceeds its fair value less cost to sell. If an impairment indicator exists, we compare the asset’s expected future undiscounted cash flows to its current carrying value to assess whether impairment measurement is necessary. Upon determination that an impairment has occurred, we recognize an impairment loss to the extent the carrying amount exceeds the estimated fair value of the real estate and other long-lived assets. During 2023, we recognized a non-cash impairment loss on real estate of $23.6 million. We did not recognize any such impairment during the years ended December 31, 2022 and 2021. The measurement of impairment is based on the fair value of the community and incorporates various estimates, assumptions, and market data, the most significant being rental rates, operating expense assumptions, expected hold period, capitalization rate, and purchase and sale agreements. We project future rental revenue growth rates using forecasted rates from third-party market research analytics. Property expense growth rates and capitalization rates are based on the apartment communities’ historical, current, and expected future operating results, existing operating expense assumptions, and operational strategies. These projections are adjusted to reflect current economic conditions and require considerable management judgment.
Cash, Cash Equivalents and Restricted Cash	Cash and Cash Equivalents We classify highly liquid investments with an original maturity of three months or less as cash equivalents. We maintain cash equivalents in financial institutions in excess of insured limits. We have not experienced any losses in these accounts in the past and believe that we are not exposed to significant credit risk because our accounts are deposited with major financial institutions. Restricted Cash As of December 31, 2023, restricted cash primarily consists of capital replacement reserves, completion repair reserves, real estate tax, insurance escrow accounts held by lenders, and resident security deposits. As of December 31, 2022, restricted cash primarily consists of cash deposited into 1031 exchange accounts in connection with tax-deferred exchange transactions that were released in conjunction with the Southgate Towers acquisition in January 2023 and the items above.
Goodwill	Goodwill As of December 31, 2023 and 2022, goodwill associated with our reportable segments totaled $32.3 million. We perform an impairment test of goodwill annually, or when an interim triggering event occurs, by evaluating qualitative factors and quantitative factors, if necessary, to determine the likelihood that goodwill may be impaired. As a result of our annual impairment test, we determined that our goodwill was not impaired during the years ended December 31, 2023, 2022, and 2021.
Investments in Unconsolidated Real Estate Partnerships	Investment in Unconsolidated Real Estate Partnerships We may own general and limited partner interests in partnerships that either directly, or through interests in other real estate partnerships, own apartment communities. We generally account for investments in real estate partnerships that we do not consolidate under the equity method. Under the equity method, we recognize our share of the earnings or losses of the entity for the periods presented, inclusive of our share of any impairments and disposition gains or losses recognized by and related to such entities, and we present such amounts within income from unconsolidated real estate partnerships in our consolidated statements of operations. Investment in unconsolidated real estate partnerships is included as a separate line item in our consolidated balance sheets. Investments in unconsolidated real estate partnerships are reviewed for impairments. An impairment loss is recorded when there is a decline in the fair value below the carrying value and we conclude such decline is other-than-temporary. An impairment loss is measured based on the excess of the carrying amount of an investment over its estimated fair value. We determine the fair value of investments in unconsolidated real estate partnerships using valuation techniques that consider the terms of the in-place leases, current market data for comparable leases, our experience in leasing similar communities, and current plans. We recognized no such impairments for any of the years ended December 31, 2023, 2022, and 2021. The excess of our cost of the acquired partnership interests over our share of the partners’ equity or deficit are included as a part of our investments in unconsolidated real estate partnerships. We amortize the excess cost over the term of the joint venture agreement. The amortization is recorded as an adjustment of the amounts of earnings or losses we recognize from such unconsolidated real estate partnerships. Please see Note 6 for further discussion regarding our investment in unconsolidated real estate partnerships.
Noncontrolling Interests in Consolidated Real Estate Partnerships	Noncontrolling Interests in Consolidated Real Estate Partnerships We generally report the unaffiliated partners’ interests in the net assets of our consolidated real estate partnerships as noncontrolling interests in consolidated real estate partnerships within consolidated equity and partners’ capital. If a real estate partnership includes redemption rights that are not within AIR and the AIR Operating Partnership’s control, the noncontrolling interest is included as temporary equity or temporary capital. The assets of real estate partnerships consolidated by the AIR Operating Partnership must first be used to settle the liabilities of such consolidated real estate partnerships. These consolidated real estate partnerships’ creditors do not have recourse to the general credit of the AIR Operating Partnership. Noncontrolling interests in consolidated real estate partnerships consist primarily of equity interests held by limited partners in consolidated real estate partnerships that have finite lives. We generally attribute to noncontrolling interests their share of income or loss of consolidated partnerships based on their proportionate interest in the results of operations of the partnerships, including their share of losses even if such attribution results in a deficit noncontrolling interest balance within our equity and partners’ capital accounts. The terms of the related partnership agreements generally require the partnerships to be liquidated following the sale of the underlying real estate. As the general partner in these partnerships, we ordinarily control the execution of real estate sales and other events that could lead to the liquidation, redemption or other settlement of noncontrolling interests. Changes in our ownership interest in consolidated real estate partnerships generally consist of our purchase of an additional interest in or the sale of our entire or partial interest in a consolidated real estate partnership. The effect on our equity and partners’ capital of our purchase of additional interests in consolidated real estate partnerships during the years ended December 31, 2023, 2022, and 2021, is shown in our consolidated statements of equity and partners’ capital. The effect on our equity and partners’ capital of sales of consolidated real estate or sales of our entire interest in consolidated real estate partnerships is reflected in our consolidated statements of operations as gains or losses on dispositions of real estate and accordingly the effect on our equity and partners’ capital is reflected within the amount of net income allocated to us and to noncontrolling interests. Upon our deconsolidation of a real estate partnership following the sale of our partnership interests or liquidation of the partnership following sale of the related apartment community, we derecognize any remaining noncontrolling interest of the associated partnership previously recorded in our consolidated balance sheets.
Noncontrolling Interests in the AIR Operating Partnership	Noncontrolling Interests in the AIR Operating Partnership Noncontrolling interests in the AIR Operating Partnership consist of common OP Units and preferred OP Units and are reflected in AIR’s accompanying consolidated balance sheets as noncontrolling interests in AIR Operating Partnership. Holders of preferred OP Units participate in the AIR Operating Partnership’s income or loss only to the extent of their preferred distributions. Within AIR’s consolidated financial statements, after provision for preferred OP Unit distributions, the AIR Operating Partnership’s income or loss is allocated to the holders of common OP Units based on the weighted-average number of common OP Units (including those held by AIR) outstanding during the period. During the years ended December 31, 2023, 2022, and 2021, the holders of common OP Units (excluding those held by AIR) had a weighted-average economic ownership interest in the AIR Operating Partnership of 6.37%, 6.25%, and 6.07%, respectively. Please refer to Note 9 for further information regarding the items comprising noncontrolling interests in the AIR Operating Partnership. Substantially all of the assets and liabilities of AIR are those of the AIR Operating Partnership.
Revenue from Leases	Revenue from Leases
Insurance	Insurance We believe our insurance coverages insure our apartment communities adequately against the risk of loss attributable to fire, earthquake, hurricane, tornado, flood, and other perils. In addition, we have third-party insurance coverage (after self-insured retentions) that defray the costs of large workers’ compensation, health, and general liability exposures. We accrue losses based upon our estimates of the aggregate liability for uninsured losses incurred using certain actuarial assumptions followed in the insurance industry and based on our experience.
Depreciation and Amortization	Depreciation and Amortization Depreciation for all tangible assets is calculated using the straight-line method over their estimated useful life. Acquired buildings and improvements are depreciated over a useful life based on the age, condition, and other physical characteristics of the asset. Furniture, fixtures, and equipment are generally depreciated over five years. We depreciate capitalized costs using the straight-line method over the estimated useful life of the related improvement, which is generally 5, 15, or 30 years. Purchased software and other costs related to software purchased or developed for internal use are capitalized during the application development stage and are amortized using the straight-line method over the estimated useful life of the software, generally three Certain homogeneous items that are purchased in bulk on a recurring basis, such as appliances, are depreciated using group methods that reflect the average estimated useful life of the items in each group. Except in the case of apartment community casualties, where the net book value of the lost asset is written off in the determination of casualty gains or losses, we generally do not recognize any loss in connection with the replacement of an existing apartment community component because normal replacements are considered in determining the estimated useful life used in connection with our composite and group depreciation methods.
Share-Based Compensation	Share-Based Compensation We issue various forms of share-based compensation, including stock options and restricted stock awards with service, performance or market conditions. We recognize share-based employee compensation based on the fair value on the grant date and recognize compensation cost over the awards’ requisite service periods. We reduce compensation cost related to forfeited awards in the period of forfeiture. Please refer to Note 10 for further discussion of our share-based compensation.
Income Taxes	Income Taxes AIR has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”), commencing with its taxable year ended December 31, 2020, and it intends to continue to operate in such a manner. AIR’s current and continuing qualification as a REIT depends on its ability to meet the various requirements imposed by the Code, which are related to organizational structure, distribution levels, diversity of stock ownership, and certain restrictions with regard to owned assets and categories of income. As a REIT, we are generally not subject to federal and certain state income tax on the net income that we currently distribute to stockholders. This treatment substantially eliminates the “double taxation” (at the corporate and stockholder levels) that generally results from an investment in a corporation. Even if AIR qualifies as a REIT, it may be subject to United States federal income and excise taxes in various situations, such as on undistributed income. AIR could also be subject to a 100% tax on transactions between it and a TRS (described below) that are determined to be non-arm’s length and on any net income from sales of apartment communities that are determined to be dealer-type prohibited transactions. The state and local tax laws may not conform to the United States federal income tax treatment, and AIR may be subject to state or local taxation in various state or local jurisdictions, including those in which we transact business. Any taxes imposed on us reduce our operating cash flow and net income. Certain of AIR’s operations, or a portion thereof, including property management and risk management, are conducted through taxable REIT subsidiaries, which are subsidiaries of the AIR Operating Partnership, and each of which we refer to as a TRS. A TRS is a corporate subsidiary that has elected to be a TRS instead of a REIT and, as such, is subject to United States federal corporate income tax. We use TRS entities to facilitate our ability to offer certain services and activities to our residents and investment partners that cannot be offered directly by a REIT. For our TRS entities, deferred income taxes result from temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts reported for United States federal income tax purposes, and are measured using the enacted tax rates and laws that are expected to be in effect when the differences reverse. We reduce deferred tax assets by recording a valuation allowance when we determine, based on available evidence, that it is more likely than not that the assets will not be realized. We recognize the tax consequences associated with intercompany transfers between the AIR Operating Partnership and TRS entities when such transactions occur. Please refer to Note 11 for further information about our income taxes.
Earnings Per Share and Unit	Earnings per Share and Unit AIR and the AIR Operating Partnership calculate earnings per share and unit, respectively, based on the weighted-average number of shares of Common Stock or common OP units, participating securities, Common Stock or common unit equivalents, and dilutive convertible securities outstanding during the period. The AIR Operating Partnership considers both common OP units and equivalents, which have identical rights to distributions and undistributed earnings, to be common units for purposes of the earnings per unit computations. Please refer to Note 12 for further information regarding earnings per share and unit computations.
Use of Estimates	Use of Estimates The preparation of our consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts included in the consolidated financial statements and accompanying notes thereto. Actual results could differ from those estimates.
Accounting Pronouncements Recently Issued	Accounting Pronouncements Recently Issued In November 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2023-07, “Segment Reporting – Improvements to Reportable Segments Disclosures.” The amendments enhance disclosures of significant segment expenses by requiring to disclose significant segment expenses regularly provided to the chief operating decision maker ("CODM"), extend certain annual disclosures to interim periods, and permit more than one measure of segment profit or loss to be reported under certain conditions. The amendments are effective for AIR in fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption of the amendment is permitted, including adoption in any interim periods for which financial statements have not been issued. AIR is currently evaluating the guidance and its impact to the consolidated financial statements. In December 2023, the FASB issued ASU No. 2023-09, "Improvements to Income Tax Disclosures," which requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as information on income taxes paid. The standard is intended to benefit investors by providing more detailed income tax disclosures that would be useful in making capital allocation decisions. This ASU is effective for public companies with annual periods beginning after December 15, 2024, with early adoption permitted. AIR is currently evaluating the guidance and its impact to the consolidated financial statements. Accounting standards that have been issued by the FASB, or other standards-setting bodies, that are not yet effective or discussed above are not expected to have a material impact on the Company’s consolidated financial statements upon adoption.
Impairment	Impairment Real estate and other long-lived assets to be held and used are individually evaluated for impairment when conditions exist that may indicate the carrying amount of a long-lived asset may not be recoverable. Impairment indicators include significant fluctuations in rental and other property revenues less property operating expenses, occupancy changes, significant near-term lease expirations, current and historical cash flow losses, rental rates, and if applicable, a comparison of an asset’s carrying value to its estimated fair value. Upon determination that an impairment has occurred, we recognize an impairment loss to the extent the carrying amount exceeds the estimated fair value of the community.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Other Assets, Net	As of December 31, 2023 and 2022, other assets, net was comprised of the following amounts (in thousands): 2023 2022 Mezzanine investment (1) $ — $ 158,726 Right-of-use lease assets 114,740 126,020 Other receivables, net 69,558 69,944 Other 99,622 195,131 Total other assets, net $ 283,920 $ 549,821 (1) Please see Note 15
Summary of Accrued Liabilities and Others	As of December 31, 2023 and 2022, accrued liabilities and other was comprised of the following amounts (in thousands): 2023 2022 Mezzanine liability (1) $ — $ 158,726 Accrued expenses 234,679 225,888 Other 62,215 129,191 Total accrued liabilities and other $ 296,894 $ 513,805 (1) Please see Note 1 5 for further discussion regarding our Mezzanine liability.

Significant Transactions (Table

Significant Transactions (Tables)	12 Months Ended
	Dec. 31, 2023
Significant Transactions [Abstract]
Schedule of Acquisition	Summarized information regarding these acquisitions is set forth in the table below (dollars in thousands) as of December 31, 2023: Number of apartment communities 3 Number of apartment homes 1,115 Purchase price $ 452,500 Capitalized transaction costs 6,739 Total consideration (1) $ 459,239 Land $ 118,564 Building and improvements 318,364 Intangible assets (2) 17,845 Mark-to-market on debt assumed 7,370 Below-market lease liabilities (2) (2,904) Total consideration (1) $ 459,239 (1) Total consideration for the apartment community acquisition in South Florida includes $101.2 million of debt assumed and the issuance of $22.4 million in common OP Units, which represent non-cash financing. (2) Intangible assets and below-market lease liabilities for the South Florida apartment community acquisition have a weighted-average term of 1.4 years and 0.5 years, respectively. Intangible assets and below-market lease liabilities for the North Carolina apartment community acquisitions have a weighted-average term of 0.5 years.
Summary of Apartment Community Sold	Sold apartment communities during the years ended December 31, 2023, 2022, and 2021, are summarized below (dollars in thousands): 2023 2022 2021 Number of apartment communities sold 3 18 16 Number of apartment homes sold 257 3,364 1,395 Gain on apartment community sales (1) $ — $ 939,806 $ 243,369 (1) The apartment communities sold during the year ended December 31, 2023 generated net proceeds of $52.1 million, which approximated their carrying value.

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Lease Income for Operating Leases	Our total lease income was comprised of the following amounts for all operating leases for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Fixed lease income $ 752,068 $ 715,060 $ 685,423 Variable lease income 56,060 47,358 46,246 Total lease income $ 808,128 $ 762,418 $ 731,669
Future Minimum Annual Rental Payments Receivable Under Residential and Commercial Leases	As of December 31, 2023, future minimum annual rental payments we are contractually obligated to receive under residential and commercial leases, excluding such extension options, are as follows (in thousands): 2024 $ 420,571 2025 85,348 2026 12,975 2027 11,066 2028 9,411 Thereafter 30,685 Total $ 570,056
Minimum Annual Rental Payments Under these Operating Leases	As of December 31, 2023, minimum annual rental payments under these operating leases, reconciled to the lease liability included in accrued liabilities and other in our consolidated balance sheets, are as follows (in thousands): 2024 $ 8,053 2025 8,084 2026 8,390 2027 8,344 2028 20,945 Thereafter 1,695,808 Total 1,749,624 Less: Discount 1,613,987 Total lease liability $ 135,637

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Summary of Non-Recourse Property Loans Payable Related to Properties	The following table summarizes our total consolidated indebtedness as of December 31, 2023 and 2022 (in thousands): 2023 2022 Secured debt: Fixed-rate property debt due May 2025 to January 2055 (1) $ 2,236,975 $ 1,906,151 Variable-rate property debt — 88,500 Total non-recourse property debt 2,236,975 1,994,651 Debt issuance costs, net of accumulated amortization (13,184) (9,221) Total non-recourse property debt, net $ 2,223,791 $ 1,985,430 Unsecured debt: Term loans due December 2024 to April 2026 (2) 475,000 800,000 Revolving credit facility borrowings due April 2025 (3) 115,000 462,000 4.58% Notes payable due June 2027 100,000 100,000 4.77% Notes payable due June 2029 100,000 100,000 4.84% Notes payable due June 2032 200,000 200,000 Total unsecured debt 990,000 1,662,000 Debt issuance costs, net of accumulated amortization (3,447) (5,801) Total unsecured debt, net 986,553 1,656,199 Total indebtedness $ 3,210,344 $ 3,641,629 (1) In the first quarter of 2023, AIR borrowed $320 million using 10-year fixed rate financing, bearing interest at 4.9%. Proceeds were used to refinance a floating rate loan and reduce borrowings by $230 million on our revolving credit facility. The stated rates on our fixed-rate property debt are between 2.7% to 5.7%. (2) The term loans bear interest at a one-month Term Secured Overnight Financing Rate (“SOFR”) plus 1.00% and a SOFR adjustment of 10-basis points, based on our current credit rating. As of December 31, 2023, the weighted-average interest rate for our term loans before consideration of in place interest rate swaps was 6.5%. As of December 31, 2023, our entire $475 million term loan balance is fixed via interest rate swaps at a weighted-average interest rate of 4.3%. The term loans mature on the following schedule: $125 million matures on December 15, 2024, with a one (3) As of December 31, 2023, we had capacity to borrow up to $880.7 million under our revolving credit facility after consideration of undrawn letters of credit. The revolving credit facility bears interest at a one-month Term SOFR plus 0.89%, based on our current credit rating, and a SOFR adjustment of 10-basis points. As of December 31, 2023, the weighted-average interest rate for our revolving credit facility was 6.3%. Subsequent to the year ended December 31, 2023, we entered into interest rate swaps economically hedging $200 million of our revolving credit facility borrowings at 4.9%.
Scheduled of principal amortization and maturity payments for our outstanding debt balances	As of December 31, 2023, the scheduled principal amortization and maturity payments for our outstanding debt balances were as follows (in thousands): Amortization Maturities Total 2024 (1) $ 31,823 $ — $ 31,823 2025 (1) (2) 29,146 646,323 675,469 2026 (1) 23,625 361,950 385,575 2027 21,071 163,098 184,169 2028 15,537 189,652 205,189 Thereafter 189,352 1,440,398 1,629,750 Total $ 310,554 $ 2,801,421 $ 3,111,975 (1) Amounts presented above are inclusive of extension options on our terms loans, as outlined above. (2) The table above excludes our revolving credit facility due April 2025, which had an outstanding balance of $115.0 million as of December 31, 2023.

Investments in Unconsolidated_2

Investments in Unconsolidated Real Estate Partnerships (Tables)	12 Months Ended
	Dec. 31, 2023
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Virginia JV Value-Add JV (1) Core JV Initial formation date October 2021 June 2023 July 2023 AIR Ownership 20% 30% 53% Outside entities ownership 80% 70% 47% Number of apartment communities 3 1 11 Apartment units 1,748 443 3,549 (1) The purchaser acquired a 70% legal ownership in the Huntington Gateway property, but AIR is entitled to 50% of the net cash flows from operations, and various fees for providing property management, construction, and corporate services to the joint venture. December 31, 2023 Virginia JV Value-Add JV Core JV Net real estate $ 467,020 $ 131,339 $ 1,258,307 Other assets, net 7,061 7,368 41,882 Total assets $ 474,081 $ 138,707 $ 1,300,189 Third-party debt $ 395,000 $ 88,741 $ 793,910 Accrued liabilities and other 4,070 2,528 10,298 Total liabilities $ 399,070 $ 91,269 $ 804,208 Total equity $ 75,011 $ 47,438 $ 495,981 AIR's investment in balance (1) $ 17,212 $ 28,606 $ 268,931 (1) AIR's investment in balance includes certain basis differences that are subject to amortization. AIR's investment in unconsolidated real estate partnerships in our consolidated balance sheets also includes $21.3 million related to two immaterial unconsolidated investments. December 31, 2022 Virginia JV Value-Add JV Core JV Net real estate $ 481,939 $ — $ — Other assets, net 10,841 — — Total assets $ 492,780 $ — $ — Third-party debt $ 395,000 $ — $ — Accrued liabilities and other 5,179 — — Total liabilities $ 400,179 $ — $ — Total equity $ 92,601 $ — $ — AIR's investment in balance (1) $ 20,684 $ — $ — (1) AIR's investment in unconsolidated real estate partnerships in our consolidated balance sheets includes $21.2 million related to two immaterial unconsolidated investments. The following tables summarize the financial information related to the Joint Venture Entities for the years ended December 31, 2023, 2022, and 2021 (in thousands): December 31, 2023 Virginia JV Value-Add JV Core JV Total revenues $ 44,725 $ 6,665 $ 51,341 Total expenses 64,779 12,969 94,141 Net loss $ (20,054) $ (6,304) $ (42,800) AIR's loss from unconsolidated real estate partnerships $ (3,999) $ (2,772) $ (22,877) December 31, 2022 Virginia JV Value-Add JV Core JV Total revenues $ 41,422 $ — $ — Total expenses 57,316 — — Net loss $ (15,894) $ — $ — AIR's loss from unconsolidated real estate partnerships $ (3,504) $ — $ — December 31, 2021 Virginia JV Value-Add JV Core JV Total revenues $ 7,471 $ — $ — Total expenses 11,414 — — Net loss $ (3,943) $ — $ — AIR's loss from unconsolidated real estate partnerships $ (565) $ — $ —

Partners' Capital (Tables)

Partners' Capital (Tables)	12 Months Ended
	Dec. 31, 2023
Partners' Capital [Abstract]
Classes of Preferred OP Units	As of December 31, 2023 and 2022, the AIR Operating Partnership had the following classes of preferred OP Units (stated at their redemption values, in thousands, except unit and per unit data): Distributions per Annum Units Issued and Redemption Values Class of Preferred Units Percent Per Unit 2023 2022 2023 2022 Class One 8.75 % $ 8.00 90,000 90,000 $ 8,229 $ 8,229 Class Two 1.92 % $ 0.48 5,368 5,418 132 135 Class Three 7.88 % $ 1.97 1,310,902 1,310,902 32,772 32,772 Class Four 8.00 % $ 2.00 644,954 644,954 16,124 16,124 Class Six 8.50 % $ 2.13 769,585 769,585 19,240 19,240 Class Seven 7.87 % $ 1.97 25,715 25,715 643 643 Total 2,846,524 2,846,574 $ 77,140 $ 77,143
Reconciliation of Preferred OP Units	The following table presents a rollforward of the AIR Operating Partnership’s preferred OP Units’ redemption value (in thousands): Balance at January 1, 2023 $ 77,143 Preferred distributions (6,280) Redemption of preferred units and other (3) Net income allocated to preferred units 6,280 Balance at December 31, 2023 $ 77,140

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Total Compensation Cost Recognized for Share-Based Awards	Total compensation cost recognized for share-based awards was as follows for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Share-based compensation expense (1) $ 8,874 $ 7,463 $ 7,360 Capitalized share-based compensation (2) 422 503 295 Total share-based compensation (3) $ 9,296 $ 7,966 $ 7,655 (1) Amounts are recorded in general and administrative expenses and property management expenses in our consolidated statements of operations. (2) Amounts are recorded in building and improvements in our consolidated balance sheets. (3) Amounts are recorded in additional paid-in capital and common noncontrolling interests in AIR Operating Partnership in the AIR consolidated balance sheets, and in general partner and special limited partner and limited partners in the AIR Operating Partnership consolidated balance sheets.
Assumptions Used in Determination of Grant-Date Fair Value of Awards	The valuation assumptions for the 2023, 2022, and 2021 grants were as follows: 2023 2022 2021 Grant date market value of a common share $ 38.26 $ 53.91 $ 36.84 Risk-free interest rate 3.85%- 4.14% 1.20% - 1.68% 0.24% - 0.78% Dividend yield 4.70 % 3.50 % 4.00 % Expected volatility 28.56% - 28.59% 22.63% - 24.83% 23.08% - 28.21% Derived vesting period of TSR Restricted Stock and TSR LTIP I units 3.5 years 3.5 years 3.2 years Weighted average expected term of TSR Stock Options and LTIP II units 5.5 years 5.4 years 5.4 years

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Components of Income Tax Benefit or Expense	Significant components of the income tax benefit or expense are as follows and are classified within income tax (expense) benefit in our consolidated statements of operations for the years ended December 31, 2023, 2022, and 2021 (in thousands): 2023 2022 2021 Current: Federal $ (1,349) $ (756) $ 7,409 State (952) (2,807) (1,971) Total current (2,301) (3,563) 5,438 Deferred: Federal (102) (291) (153) State (24) (69) (39) Total deferred (126) (360) (192) Total (expense) benefit $ (2,427) $ (3,923) $ 5,246
Reconciliation of Income Tax Attributable to Operations	The reconciliation of income tax computed at the United States statutory rate to income tax benefit is shown below (dollars in thousands): 2023 2022 2021 Amount Percent Amount Percent Amount Percent Tax expense provision at United States statutory rates on consolidated income from continuing operations subject to tax $ (5,065) (21.0 %) $ (1,554) (21.0 %) $ (6,064) (21.0 %) State income tax expense, net of federal tax expense (996) (4.1 %) (2,853) (38.6 %) (2,011) (7.0 %) Tax credits 3,420 14.2 % 191 2.6 % 3,508 12.1 % TRS REIT election — — % — — % 9,656 33.4 % Other 214 0.9 % 293 4.0 % 157 0.5 % Total income tax expense $ (2,427) (10.0 %) $ (3,923) (53.0 %) $ 5,246 18.0 %
Schedule of Dividends Per Share Held	For the years ended December 31, 2023, 2022, and 2021, dividends per share held for the entire year were estimated to have the following tax attributes: 2023 2022 2021 (unaudited) Amount Percentage Amount Percentage Amount Percentage Ordinary income $ 0.24 13.1 % $ 0.21 11.8 % $ — — % Capital gains 0.06 3.5 % 1.37 76.0 % 0.44 25.3 % Qualified dividends — — % 0.03 1.9 % — —% Unrecaptured Section 1250 gain — — % 0.19 10.3 % 0.13 7.5 % Return of capital 1.50 83.4 % — — % 1.17 67.2 % Total $ 1.80 100.0 % $ 1.80 100.0 % $ 1.74 100.0 %

Earnings and Dividends per Sh_2

Earnings and Dividends per Share and per Unit (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Reconciliations of Numerator and Denominator in Calculations of Basic and Diluted Earnings per Share and per Unit	Reconciliations of the numerator and denominator in the calculations of basic and diluted earnings per share and per unit for the years ended December 31, 2023, 2022, and 2021 are as follows (in thousands, except per share and per unit data): 2023 2022 2021 Earnings per share Numerator: Basic and dilutive net income attributable to AIR common stockholders $ 634,444 $ 903,642 $ 447,124 Effect of dilutive instruments 6,280 6,388 — Dilutive net income attributable to AIR common stockholders $ 640,724 $ 910,030 $ 447,124 Denominator – shares: Basic weighted-average common shares outstanding 147,899 154,093 154,135 Dilutive common share equivalents outstanding 2,321 2,494 368 Dilutive weighted-average common shares outstanding 150,220 156,587 154,503 Earnings per share – basic $ 4.29 $ 5.86 $ 2.90 Earnings per share – diluted $ 4.27 $ 5.81 $ 2.89 Earnings per unit Numerator: Basic and dilutive net income attributable to the AIR Operating Partnership’s common unitholders $ 677,165 $ 962,414 $ 475,557 Effect of dilutive instruments 6,280 6,388 — Basic and dilutive net income attributable to the AIR Operating Partnership’s common unitholders $ 683,445 $ 968,802 $ 475,557 Denominator – units: Basic weighted-average common units outstanding 157,687 164,141 162,739 Dilutive common unit equivalents outstanding 2,321 2,494 369 Dilutive weighted-average common units outstanding 160,008 166,635 163,108 Earnings per unit – basic $ 4.29 $ 5.86 $ 2.92 Earnings per unit – diluted $ 4.27 $ 5.81 $ 2.92

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Summary of Fair Value for Interest Rate Options and swaps	The following table summarizes investments measured at fair value on a recurring basis, which are presented in other assets, net, and accrued liabilities and other in our consolidated balance sheets (in thousands): As of December 31, 2023 As of December 31, 2022 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Interest rate option (1) $ — $ — $ — $ — $ 53,481 $ — $ 53,481 $ — Interest rate swaps - pay-fixed, receive floating $ 14,679 $ — $ 14,679 $ — $ 32,222 $ — $ 32,222 $ — Interest rate swaps - pay-floating, receive fixed $ 465 $ — $ 465 $ — $ — $ — $ — $ — Interest rate swap - forward starting $ 331 $ — $ 331 $ — $ — $ — $ — $ — Treasury rate locks $ — $ — $ — $ — $ 319 $ — $ 319 $ — (1) During the second quarter of 2023, the interest rate swap option asset and offsetting liability associated with the Parkmerced mezzanine investment was settled, resulting in equal decreases in other assets and accrued liabilities and other in the consolidated balance sheets which represents non-cash activity.
Summary of Carrying Value and Fair Value of Non-recourse Property Debt	We classify the fair value of our non-recourse property debt, unsecured notes payable, seller financing notes receivable, and preferred equity investment within Level 2 of the GAAP fair value hierarchy, as summarized in the following table (in thousands): As of December 31, 2023 As of December 31, 2022 Carrying Value Fair Value Carrying Value Fair Value Non-recourse property debt $ 2,236,975 $ 2,001,532 $ 1,994,651 $ 1,753,222 Unsecured notes payable $ 400,000 $ 384,244 $ 400,000 $ 371,368 Seller financing note receivable, net (1) $ 32,459 $ 33,042 $ 31,611 $ 32,286 Preferred equity investment (2) $ 22,693 $ 23,562 $ — $ — (1) During the year ended December 31, 2022, we provided $40.0 million of seller financing as partial consideration for the sale of our New England portfolio. The contractual interest rate on the note is 4.5%. The difference between the stated rate and the market interest rate as of the date of sale resulted in a discount recorded of $8.5 million. The seller financing note and related discount are included in other assets, net in our consolidated balance sheets. (2)

Derivative Financial Instrume_2

Derivative Financial Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Derivative Financial Instrument and Hedging Activities	The following table summarizes our derivative financial instruments (dollars in thousands): As of December 31, 2023 Number of Aggregate Notional Derivative Assets Derivative Liabilities Instruments Amount Fair Value Derivatives not designated as hedging instruments: Interest rate swaps - pay-fixed, receive floating 7 $ 555,000 $ 15,266 $ (587) Interest rate swaps - pay-floating, receive fixed 2 $ 80,000 $ 472 $ (7) Interest rate swap, forward starting 1 $ 50,000 $ 331 $ — As of December 31, 2022 Number of Aggregate Notional Derivative Assets Derivative Liabilities Instruments Amount Fair Value Derivatives designated as hedging instruments: Treasury rate lock 1 $ 100,000 $ 319 $ — Interest rate swaps - pay-fixed, receive floating 10 $ 830,000 $ 32,222 $ —

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Variable Interest Entities	The table below summarizes apartment community information regarding VIEs consolidated by the AIR Operating Partnership: December 31, 2023 (1) December 31, 2022 VIEs with interests in apartment communities 3 5 Apartment communities owned by VIEs 14 16 Apartment homes in communities owned by VIEs 4,866 5,369 (1) During 2023, the number of our VIEs with interests in apartment communities decreased due to our Core JV partner's acquisition of an indirect 47% interest through the Core JV in one consolidated limited partnership with 175 apartment homes, and our purchase of the remaining non-controlling interest in a consolidated limited partnership with 328 apartment homes, which was subsequently contributed to the Core JV during the third quarter of 2023. Assets of the AIR Operating Partnership’s consolidated VIEs must first be used to settle the liabilities of such consolidated VIEs. These consolidated VIEs’ creditors do not have recourse to the general credit of the AIR Operating Partnership. Assets and liabilities of VIEs, excluding those of the AIR Operating Partnership, are summarized in the table below (in thousands): December 31, 2023 December 31, 2022 ASSETS: Net real estate $ 1,013,770 $ 1,066,482 Cash and cash equivalents 41,219 54,319 Restricted cash 2,179 2,378 Other assets, net 22,546 20,944 LIABILITIES: Non-recourse property debt, net $ 1,196,280 $ 1,212,065 Accrued liabilities and other 34,903 35,365

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Summary of Information for Reportable Segments	The following tables present the total revenues, property operating expenses, proportionate property net operating income (loss), and income before income tax expense of our segments on a proportionate basis, excluding amounts related to communities sold. To reflect how the CODM evaluates the business, prior period segment information has been recast to conform with our reportable segment composition as of December 31, 2023 (in thousands): Same Other Proportionate Corporate and Consolidated Year ended December 31, 2023: Total revenues $ 600,142 $ 119,587 $ 85,825 $ 14,482 $ 820,036 Property management and operating expenses 152,898 37,899 44,295 40,740 275,832 Other operating expenses not allocated to segments (3) — — — 393,976 393,976 Total operating expenses 152,898 37,899 44,295 434,716 669,808 Proportionate property net operating income (loss) 447,244 81,688 41,530 (420,234) 150,228 Other items included in income before income tax expense (4) — — — 541,486 541,486 Income before income tax expense $ 447,244 $ 81,688 $ 41,530 $ 121,252 $ 691,714 Same Other Proportionate Corporate and Consolidated Year ended December 31, 2022: Total revenues $ 556,318 $ 37,783 $ 125,800 $ 53,822 $ 773,723 Property management and operating expenses 147,084 12,399 51,350 50,431 261,264 Other operating expenses not allocated to segments (3) — — — 384,957 384,957 Total operating expenses 147,084 12,399 51,350 435,388 646,221 Proportionate property net operating income (loss) 409,234 25,384 74,450 (381,566) 127,502 Other items included in income before income tax expense (4) — — — 846,471 846,471 Income before income tax expense $ 409,234 $ 25,384 $ 74,450 $ 464,905 $ 973,973 Same Other Proportionate Corporate and Consolidated Year ended December 31, 2021: Total revenues $ 499,896 $ — $ 113,634 $ 127,323 $ 740,853 Property management and operating expenses 140,829 — 48,101 79,171 268,101 Other operating expenses not allocated to segments (3) — — — 365,547 365,547 Total operating expenses 140,829 — 48,101 444,718 633,648 Proportionate property net operating income (loss) 359,067 — 65,533 (317,395) 107,205 Other items included in income before income tax expense (4) — — — 366,773 366,773 Income before income tax expense $ 359,067 $ — $ 65,533 $ 49,378 $ 473,978 (1) Represents adjustments to: (i) exclude AIR’s proportionate share of the results of unconsolidated apartment communities, which is excluded in the related consolidated amounts, and (ii) include the noncontrolling interests in consolidated real estate partnerships’ proportionate share of the results of communities, which is included in the related consolidated amounts. Also includes the reclassification of utility reimbursements from revenues to property operating expenses for the purpose of evaluating segment results. Utility reimbursements are included in rental and other property revenues in our consolidated statements of operations prepared in accordance with GAAP. (2) Includes: (i) the operating results of apartment communities sold during the periods shown or held for sale at the end of the period, if any, (ii) property management revenues, which are not part of our segment performance measure, property management expenses and casualty gains and losses, which are included in consolidated property management and operating expenses and are not part of our segment performance measure, and (iii) the depreciation of capitalized costs of non-real estate assets. (3) Includes depreciation and amortization, general and administrative expenses, and other expenses, net, and may also include write-offs of deferred leasing commissions, which are not included in our measure of segment performance. (4) Includes interest income, interest expense, loss on extinguishment of debt, gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties, loss from unconsolidated real estate partnerships, and gain on derivative instruments, net.
Reconciliation of Assets from Segment to Consolidated	The assets of our segments and the consolidated assets not allocated to our segments were as follows (in thousands): December 31, 2023 December 31, 2022 Same Store $ 4,131,039 $ 4,610,356 Other Real Estate 1,519,326 1,211,136 Corporate and other assets (1) 484,387 730,391 Total consolidated assets $ 6,134,752 $ 6,551,883 (1)
Capital Additions Related to Segments	Capital additions related to our segments were as follows (in thousands): 2023 2022 2021 Same Store $ 134,850 $ 145,881 $ 130,207 Other Real Estate 20,724 3,825 — Total capital additions $ 155,574 $ 149,706 $ 130,207

Basis of Presentation and Org_2

Basis of Presentation and Organization (Details)	12 Months Ended
	Dec. 31, 2023 apartment property stateAndDistrict shares	Dec. 31, 2022 shares
Real Estate Properties [Line Items]
Number of states and district | stateAndDistrict	10
Apartment units | apartment	20,886
Common stock, shares outstanding (in shares)	144,925,604	149,086,548
Common stock, shares issued (in shares)	144,925,604	149,086,548
AIR Operating Partnership
Real Estate Properties [Line Items]
Common operating partnership units and equivalents outstanding, (in shares)	159,130,441
Percentage of the Aimco Operating Partnership's common partnership units and equivalents owned by Aimco	91.10%
Percentage of economic interest	93.60%
Partially Owned Properties
Real Estate Properties [Line Items]
Number of apartment communities | property	75
Apartment units | apartment	26,626
Percentage of average ownership of portfolio	81%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) account entity	Dec. 31, 2022 USD ($) entity	Dec. 31, 2021 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of consolidated VIEs | entity	5	7
Interest costs capitalized	$ 1,100,000	$ 1,500,000	$ 2,400,000
Other direct and indirect costs capitalized	16,200,000	16,600,000	10,300,000
Provision for real estate impairment loss	$ 0	0	0
Number of exchange accounts | account	1,031
Goodwill	$ 32,286,000	32,286,000
Percentage of income tax on income from non-arms length transactions	10,000%
Other Real Estate
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Provision for real estate impairment loss	$ 23,600,000	$ 0	$ 0
Minimum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	5 years
Median
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	15 years
Maximum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	30 years
Furniture, Fixtures and Equipment
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	5 years
Software and Software Development Costs | Minimum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	3 years
Software and Software Development Costs | Maximum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	5 years
Purchased Equipment
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	5 years
AIMCO
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Weighted average ownership interest	6.37%	6.25%	6.07%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Other Assets, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Mezzanine investment	$ 0	$ 158,726
Right-of-use lease assets	$ 114,740	$ 126,020
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Total other assets, net	Total other assets, net
Other receivables, net	$ 69,558	$ 69,944
Other	99,622	195,131
Total other assets, net	$ 283,920	$ 549,821

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Summary Of Accrued Liabilities And Other (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Mezzanine liability	$ 0	$ 158,726
Accrued expenses	234,679	225,888
Other	62,215	129,191
Total accrued liabilities and other	$ 296,894	$ 513,805

Significant Transactions - Narr

Significant Transactions - Narrative (Details)	2 Months Ended	12 Months Ended
	Feb. 15, 2024 USD ($) apartment property	Dec. 31, 2023 USD ($) property	Dec. 31, 2022 USD ($) property	Dec. 31, 2021 USD ($) property	Dec. 31, 2020 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net income (loss) attributable to nonredeemable noncontrolling interest		$ 5,185,000	$ 458,000	$ (3,243,000)
Provision for real estate impairment loss		0	0	0
Interest income		$ 8,314,000	50,264,000	58,651,000
AIMCO
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss					$ 534,000,000
AIMCO | The Note
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Debt instrument, interest rate, stated percentage					5.20%
Interest Income
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Interest income			13,800,000	27,800,000
Other Real Estate
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities | property		12
Provision for real estate impairment loss		$ 23,600,000	0	0
Lease Cancellation
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net income (loss) attributable to nonredeemable noncontrolling interest		$ 0	$ 17,300,000	$ 26,000,000
Wholly And Partially Owned Consolidated Properties | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities | property		3	18	16
Raleigh North Carolina
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities | property		1
Raleigh North Carolina | Subsequent Event
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities | property	1
Number of apartment homes | apartment	384
Purchase price	$ 86,500,000
Durham, North Carolina
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities | property		1

Significant Transactions - Sche

Significant Transactions - Schedule of Acquisition (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) property apartment
North Carolina And South Florida | Apartment Community
Business Acquisition [Line Items]
Number of apartment communities | property	3
Number of apartment homes | apartment	1,115
Purchase price	$ 452,500
Capitalized transaction costs	6,739
Total consideration	459,239
Land	118,564
Building and improvements	318,364
Intangible assets	17,845
Mark-to-market on debt assumed	7,370
Below-market lease liabilities	(2,904)
Total consideration	$ 459,239
South Florida
Business Acquisition [Line Items]
Number of apartment communities | property	1
Debts assumed	$ 101,200
Common OP units issuance	$ 22,400
South Florida | Below-market leases
Business Acquisition [Line Items]
Weighted-average term	6 months
South Florida | Intangible Assets
Business Acquisition [Line Items]
Weighted-average term	1 year 4 months 24 days
North Carolina | Below-market leases
Business Acquisition [Line Items]
Weighted-average term	6 months

Significant Transactions - Summ

Significant Transactions - Summary of Apartment Community Dispositions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) property apartment	Dec. 31, 2022 USD ($) property	Dec. 31, 2021 USD ($) property
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment homes sold | apartment	20,886
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Wholly And Partially Owned Consolidated Properties
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities sold | property	3	18	16
Number of apartment homes sold | property	257	3,364	1,395
Gain on apartment community sales | $	$ 0	$ 939,806	$ 243,369
Proceeds from divestiture of businesses | $	$ 52,100

Leases - Lease Income for Opera

Leases - Lease Income for Operating Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Fixed lease income	$ 752,068	$ 715,060	$ 685,423
Variable lease income	56,060	47,358	46,246
Total lease income	$ 808,128	$ 762,418	$ 731,669
Operating lease, lease income, statement of income or comprehensive income	Total revenues	Total revenues	Total revenues

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total lease liability	$ 135,637
Ground and Office Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease cost	$ 21,500	$ 15,400	$ 5,300
Ground Lease
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Weighted average remaining term	88 years
Operating lease, weighted average discount rate, percent	6.80%
Total lease liability	$ 128,100
Office Lease
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Weighted average remaining term	5 years 2 months 12 days
Operating lease, weighted average discount rate, percent	3.80%
Residential Lease
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lessee, operating lease, term of contract	8 months 21 days

Leases - Future Minimum Annual

Leases - Future Minimum Annual Payments Receivable Under Residential and Commercial Leases (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases [Abstract]
2024	$ 420,571
2025	85,348
2026	12,975
2027	11,066
2028	9,411
Thereafter	30,685
Total	$ 570,056

Leases - Aggregate Minimum Leas

Leases - Aggregate Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases [Abstract]
2024	$ 8,053
2025	8,084
2026	8,390
2027	8,344
2028	20,945
Thereafter	1,695,808
Total	1,749,624
Less: Discount	1,613,987
Total lease liability	$ 135,637
Operating Lease, Liability, Statement of Financial Position	Accrued liabilities and other

Debt - Schedule of Debt Instrum

Debt - Schedule of Debt Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2023	Feb. 15, 2024	Dec. 31, 2022	Apr. 23, 2021
Debt Instrument [Line Items]
Long-term debt, gross		$ 2,801,421
Total indebtedness		3,210,344		$ 3,641,629
Debt, weighted average interest rate					4.60%
Revolving credit facility borrowings		115,000		462,000
Secured Debt
Debt Instrument [Line Items]
Debt issuance costs, net of accumulated amortization		(13,184)		(9,221)
Total indebtedness		2,223,791		1,985,430
Unsecured debt
Debt Instrument [Line Items]
Debt issuance costs, net of accumulated amortization		(3,447)		(5,801)
Total indebtedness		986,553		1,656,199
Unsecured Debt Gross
Debt Instrument [Line Items]
Long-term debt, gross		990,000		1,662,000
Term Loan | Unsecured debt
Debt Instrument [Line Items]
Long-term debt, gross		475,000		800,000
Loan borrowed		$ 475,000
Term Loan | Unsecured debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		1%
Spread on variable interest rate		0.10%
Debt, weighted average interest rate		6.50%
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit facility borrowings		$ 880,700
Revolving Credit Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Spread on variable interest rate		0.89%
Revolving Credit Facility | Unsecured debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 115,000		462,000
Revolving Credit Facility | Unsecured debt | Subsequent Event
Debt Instrument [Line Items]
Debt, weighted average interest rate			3.90%
Revolving Credit Facility | Unsecured debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt, weighted average interest rate		6.30%
Fixed-rate property debt | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 2,236,975		1,906,151
Variable Rate Property Debt | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross		0		88,500
Non-recourse property debt | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross		2,236,975		1,994,651
4.58% Notes payable due June 2027 | Unsecured debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 100,000		$ 100,000
Debt instrument, interest rate, stated percentage		4.58%		4.58%
4.77% Notes payable due June 2029 | Unsecured debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 100,000		$ 100,000
Debt instrument, interest rate, stated percentage		4.77%		4.77%
4.84% Notes payable due June 2032 | Unsecured debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 200,000		$ 200,000
Debt instrument, interest rate, stated percentage		4.84%		4.84%
Fixed Rate Member
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.90%
Loan borrowed	$ 320,000
Loan term	10 years
Payment for borrowings	$ 230,000
Fixed Rate Member | Secured Debt | Minimum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	2.70%
Fixed Rate Member | Secured Debt | Maximum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	5.70%
Schedule Term Loan
Debt Instrument [Line Items]
Loan borrowed		$ 125,000
Long-term debt, term		1 year
Schedule Term Loan | Term Loan | Unsecured debt
Debt Instrument [Line Items]
Debt, weighted average interest rate		4.30%
Schedule Term Loan One
Debt Instrument [Line Items]
Loan borrowed		$ 150,000
Schedule Term Loan Two
Debt Instrument [Line Items]
Loan borrowed		$ 200,000
Floating Rate | Secured Debt
Debt Instrument [Line Items]
Weighted average remaining terms		2 years 1 month 6 days

Debt - Narrative (Details)

Debt - Narrative (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) apartment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Line of Credit Facility [Line Items]
Long-term debt, gross			$ 2,801,421
Non-recourse property debt, net			2,223,791	$ 1,985,430
Repayments of debt			$ 325,000	350,000	$ 350,000
Minimum
Line of Credit Facility [Line Items]
Fixed charges coverage ratio			1.50
Secured indebtedness to total assets ratio			0.40
Maximum unsecured leverage ratio			60%
Unsecured interest coverage ratio			1.50
Minimum | Leverage Ratio
Line of Credit Facility [Line Items]
Unsecured leverage ratio			0.60
Interest Expense
Line of Credit Facility [Line Items]
Debt issuance costs, gross		$ 800
Unsecured debt | Term Loan
Line of Credit Facility [Line Items]
Long-term debt, gross			$ 475,000	800,000
Repayments of debt		325,000
Core JV
Line of Credit Facility [Line Items]
Long-term debt, gross			373,300
Non-recourse property debt, net			644,400
Fifteen Year Fixed Rate Financing
Line of Credit Facility [Line Items]
Revolving credit facility	$ 1,000,000
Loan term	15 years
Line of credit, current liquidity			1,900,000
Fixed Rate Property Debt
Line of Credit Facility [Line Items]
Aggregate gross book value			$ 2,500,000
Fixed Rate Property Debt | Pledged as Collateral
Line of Credit Facility [Line Items]
Number of apartment communities | apartment			26
Fixed Rate Property Debt | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, gross			$ 2,236,975	1,906,151
Fixed Rate Property Debt | Nine Properties | Core JV | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, gross		611,400
Fixed Rate Property Debt | One Property | Core JV | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, gross		33,000
Term Loan Maturity on December 15, 2023
Line of Credit Facility [Line Items]
Repayments of debt		150,000
Term Loan Maturity on December 15, 2024
Line of Credit Facility [Line Items]
Repayments of debt		$ 175,000
Variable Rate Property Debt | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, gross			$ 0	$ 88,500

Debt - Scheduled of principal a

Debt - Scheduled of principal amortization and maturity payments for our outstanding debt balances (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortization
2024	$ 31,823
2025	29,146
2026	23,625
2027	21,071
2028	15,537
Thereafter	189,352
Total	310,554
Maturities
2024	0
2025	646,323
2026	361,950
2027	163,098
2028	189,652
Thereafter	1,440,398
Total	2,801,421
Total
2024	31,823
2025	675,469
2026	385,575
2027	184,169
2028	205,189
Thereafter	1,629,750
Total	3,111,975
Long-term debt, gross	2,801,421
Revolving Credit Facility | Unsecured debt
Maturities
Total	115,000	$ 462,000
Total
Long-term debt, gross	$ 115,000	$ 462,000

Investments in Unconsolidated_3

Investments in Unconsolidated Real Estate Partnerships - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) property apartment joint_venture unit	Jun. 30, 2023 unit	Dec. 31, 2022 USD ($)
Variable Interest Entity [Line Items]
Number of joint ventures | joint_venture	2
Apartment units | apartment	20,886
Long term debt	$ 3,210,344		$ 3,641,629
Long-term debt, gross	2,801,421
Non-recourse property debt, net	2,223,791		$ 1,985,430
Huntington Gateway
Variable Interest Entity [Line Items]
Proceeds from Real Estate and Real Estate Joint Ventures	9,000
Real Estate Investments, Joint Ventures	$ 94,100
Cash flow from operations	50%	50%
Gain on dispositions of real estate, impairments of real estate, and derecognition of leased properties	$ 1,000
Equity method investment, ownership interest sold	70%
Huntington Gateway | Apartment Income REIT, L.P
Variable Interest Entity [Line Items]
Ownership, percentage		30%
Huntington Gateway | VIRGINIA
Variable Interest Entity [Line Items]
Apartment units | unit		443
Global Institutional Investor Joint Venture
Variable Interest Entity [Line Items]
Number of properties in portfolio | property	10
Global Institutional Investor Joint Venture | Apartment Income REIT, L.P
Variable Interest Entity [Line Items]
Ownership, percentage	53%
Global Institutional Investor Joint Venture | Washington DC
Variable Interest Entity [Line Items]
Number of properties in portfolio | unit	456
Long term debt	$ 155,000
General partners' contributed capital	95,000
Purchase price	250,000
Core JV
Variable Interest Entity [Line Items]
Long term debt	1,100,000
Long-term debt, gross	373,300
Non-recourse property debt, net	644,400
Proceeds from sale of interest in partnership unit	201,900
Gain (Loss) on Sale of Interest in Projects	$ 700,500

Investments in Unconsolidated_4

Investments in Unconsolidated Real Estate Partnerships - Ownership Information (Details)	12 Months Ended
	Dec. 31, 2023 apartment community
Schedule of Equity Method Investments [Line Items]
Apartment units	20,886
Virginia JV
Schedule of Equity Method Investments [Line Items]
Number of apartment communities | community	3
Apartment units	1,748
Virginia JV | Parent Company
Schedule of Equity Method Investments [Line Items]
Ownership, percentage	20%
Virginia JV | Partnership Interest
Schedule of Equity Method Investments [Line Items]
Ownership, percentage	80%
Value-Add JV
Schedule of Equity Method Investments [Line Items]
Number of apartment communities | community	1
Apartment units	443
Value-Add JV | Parent Company
Schedule of Equity Method Investments [Line Items]
Ownership, percentage	30%
Value-Add JV | Partnership Interest
Schedule of Equity Method Investments [Line Items]
Ownership, percentage	70%
Core JV
Schedule of Equity Method Investments [Line Items]
Number of apartment communities | community	11
Apartment units	3,549
Core JV | Parent Company
Schedule of Equity Method Investments [Line Items]
Ownership, percentage	53%
Core JV | Partnership Interest
Schedule of Equity Method Investments [Line Items]
Ownership, percentage	47%
Huntington Gateway
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership interest sold	70%

Investments in Unconsolidated_5

Investments in Unconsolidated Real Estate Partnerships - Summary of Combined Balance Sheets for Joint Venture Partners (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Net real estate	$ 5,364,978	$ 5,626,511
Other assets, net	283,920	549,821
Total assets	6,134,752	6,551,883
Third-party debt	3,210,344	3,641,629
Accrued liabilities and other	296,894	513,805
Total liabilities	3,507,238	4,155,434
Total AIR equity	2,351,896	2,156,417
Investment in unconsolidated real estate partnerships	336,077	41,860
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Net real estate	1,013,770	1,066,482
Other assets, net	22,546	20,944
Accrued liabilities and other	34,903	35,365
Variable Interest Entity, Primary Beneficiary | Virginia JV
Variable Interest Entity [Line Items]
Net real estate	467,020	481,939
Other assets, net	7,061	10,841
Total assets	474,081	492,780
Third-party debt	395,000	395,000
Accrued liabilities and other	4,070	5,179
Total liabilities	399,070	400,179
Total AIR equity	75,011	92,601
Investment in unconsolidated real estate partnerships	17,212	20,684
Variable Interest Entity, Primary Beneficiary | Value-Add JV
Variable Interest Entity [Line Items]
Net real estate	131,339	0
Other assets, net	7,368	0
Total assets	138,707	0
Third-party debt	88,741	0
Accrued liabilities and other	2,528	0
Total liabilities	91,269	0
Total AIR equity	47,438	0
Investment in unconsolidated real estate partnerships	28,606	0
Variable Interest Entity, Primary Beneficiary | Core JV
Variable Interest Entity [Line Items]
Net real estate	1,258,307	0
Other assets, net	41,882	0
Total assets	1,300,189	0
Third-party debt	793,910	0
Accrued liabilities and other	10,298	0
Total liabilities	804,208	0
Total AIR equity	495,981	0
Investment in unconsolidated real estate partnerships	268,931	0
Variable Interest Entity, Not Primary Beneficiary | Immaterial Unconsolidated Investments
Variable Interest Entity [Line Items]
Investment in unconsolidated real estate partnerships	$ 21,300	$ 21,200

Investments in Unconsolidated_6

Investments in Unconsolidated Real Estate Partnerships - Income Statment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Total revenues	$ 820,036	$ 773,723	$ 740,853
Total expenses	669,808	646,221	633,648
Net loss	689,287	970,050	479,224
Loss from unconsolidated real estate partnerships	(29,648)	(3,504)	(565)
Variable Interest Entity, Primary Beneficiary | Virginia JV
Schedule of Equity Method Investments [Line Items]
Total revenues	44,725	41,422	7,471
Total expenses	64,779	57,316	11,414
Net loss	(20,054)	(15,894)	(3,943)
Loss from unconsolidated real estate partnerships	(3,999)	(3,504)	(565)
Variable Interest Entity, Primary Beneficiary | Value-Add JV
Schedule of Equity Method Investments [Line Items]
Total revenues	6,665	0	0
Total expenses	12,969	0	0
Net loss	(6,304)	0	0
Loss from unconsolidated real estate partnerships	(2,772)	0	0
Variable Interest Entity, Primary Beneficiary | Core JV
Schedule of Equity Method Investments [Line Items]
Total revenues	51,341	0	0
Total expenses	94,141	0	0
Net loss	(42,800)	0	0
Loss from unconsolidated real estate partnerships	$ (22,877)	$ 0	$ 0

AIR Equity (Details)

AIR Equity (Details) - USD ($)		12 Months Ended
	Apr. 23, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Feb. 15, 2024
Class Of Stock [Line Items]
Repurchases of common stock		$ 124,361,000	$ 316,710,000	$ 0
Common stock, shares issued (in shares)		144,925,604	149,086,548
Common stock per share (in dollars per share)	$ 43.77
Cash proceeds, net of fees	$ 342,200,000	$ 0	$ 0	$ 342,470,000
Repayment of property debt	$ 318,400,000
Weighted-average interest rate	4.60%
Subsequent Event
Class Of Stock [Line Items]
Stock Repurchase Program, Additional Authorized Repurchase Amount					$ 500,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount					$ 34,300,000
AIMCO PROPERTIES, L.P.
Class Of Stock [Line Items]
Dividends per share (in dollars per share)		$ 1.80	$ 1.80	$ 1.74
Common Class A
Class Of Stock [Line Items]
Common stock, shares issued (in shares)	7,800,000
Preferred stock, dividend rate		8.50%
Board of Directors
Class Of Stock [Line Items]
Repurchase of common stock shares		4,300,000
Repurchases of common stock		$ 149,000,000
Common stock average price, (in dollars per share)		$ 34.48
Class A Cumulative Preferred Stock
Class Of Stock [Line Items]
Preferred stock, shares issued (in shares)		20	20
Preferred stock, shares outstanding (in shares)		20	20
Outstanding principal balance of shares issued and outstanding		$ 2,000,000	$ 2,000,000
Preferred stock, par or stated value per share (in dollars per share)		$ 0.01
Preferred stock, liquidation preference, value		$ 100,000

Partners' Capital - Classes of

Partners' Capital - Classes of Preferred OP Units (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Limited Partners Capital Account [Line Items]
Units issued (in shares)	2,846,524	2,846,574
Units outstanding (in shares)	2,846,524	2,846,574
Redemption values	$ 77,140	$ 77,143
AIMCO PROPERTIES, L.P. | Class One
Limited Partners Capital Account [Line Items]
Distributions per annum	8.75%
Distributions per annum (in dollars per share)	$ 8
Units issued (in shares)	90,000	90,000
Units outstanding (in shares)	90,000	90,000
Redemption values	$ 8,229	$ 8,229
AIMCO PROPERTIES, L.P. | Class Two
Limited Partners Capital Account [Line Items]
Distributions per annum	1.92%
Distributions per annum (in dollars per share)	$ 0.48
Units issued (in shares)	5,368	5,418
Units outstanding (in shares)	5,368	5,418
Redemption values	$ 132	$ 135
AIMCO PROPERTIES, L.P. | Class Three
Limited Partners Capital Account [Line Items]
Distributions per annum	7.88%
Distributions per annum (in dollars per share)	$ 1.97
Units issued (in shares)	1,310,902	1,310,902
Units outstanding (in shares)	1,310,902	1,310,902
Redemption values	$ 32,772	$ 32,772
AIMCO PROPERTIES, L.P. | Class Four
Limited Partners Capital Account [Line Items]
Distributions per annum	8%
Distributions per annum (in dollars per share)	$ 2
Units issued (in shares)	644,954	644,954
Units outstanding (in shares)	644,954	644,954
Redemption values	$ 16,124	$ 16,124
AIMCO PROPERTIES, L.P. | Class Six
Limited Partners Capital Account [Line Items]
Distributions per annum	8.50%
Distributions per annum (in dollars per share)	$ 2.13
Units issued (in shares)	769,585	769,585
Units outstanding (in shares)	769,585	769,585
Redemption values	$ 19,240	$ 19,240
AIMCO PROPERTIES, L.P. | Class Seven
Limited Partners Capital Account [Line Items]
Distributions per annum	7.87%
Distributions per annum (in dollars per share)	$ 1.97
Units issued (in shares)	25,715	25,715
Units outstanding (in shares)	25,715	25,715
Redemption values	$ 643	$ 643

Partners' Capital - Narrative (

Partners' Capital - Narrative (Details) - AIMCO PROPERTIES, L.P. - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Redeemable partnership preferred units redeemed for cash during period (in units)	50	89,000	3,000
Common OP Units redeemed in exchange for cash during period (in units)	528,000,000	251,000	356,000
Common OP Units redeemed in exchange for shares during period		3,000	171,000
Dividends per share (in dollars per share)	$ 1.80	$ 1.80	$ 1.74

Partners' Capital - Reconciliat

Partners' Capital - Reconciliation of Preferred OP Units (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Redeemable Noncontrolling Interest [Roll Forward]
Balance at January 1, 2023	$ 77,143
Preferred distributions	(6,280)
Redemption of preferred units and other	(3)
Net income allocated to preferred units	6,280
Balance at December 31, 2023	$ 77,140

Share-Based Compensation - Narr

Share-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unvested compensation cost not yet recognized for options and restricted stock awards	$ 12.9
Weighted average period over which unvested compensation cost expected to be recognized	1 year 7 months 6 days
Grant period	10 years
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options	10 years
Stock option outstanding (in shares)	831,297
Stock options outstanding, weighted average remaining contractual term	2 years 2 months 12 days
Stock options exercisable (in shares)	718,961
Stock options exercisable, weighted average remaining contractual term	1 year 9 months 18 days
TSR Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options	10 years
Options granted, weighted average grant-date fair value (dollars per share)	$ 11.62
Options granted (in shares)		0	0
TSR LTIP Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options	10 years
TSR LTIP Units | 36 Months After Grant Date
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage, TSR restricted stock	50%
TSR LTIP Units | 48 Months After Grant Date
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage, TSR restricted stock	50%
TSR and Time-Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate fair value of restricted stock awards that vested	$ 1.7	$ 4.3	$ 3.2
TSR and Time-Based Restricted Stock Awards | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
Time-Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share unvested (in shares)	134,615
Weighted average grant fair value (in dollars per share)	$ 47.78
TSR Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share unvested (in shares)	308,327
Weighted average grant fair value (in dollars per share)	$ 43.72
TSR LTIP II Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options	10 years
Number of share unvested (in shares)	3,317,384
Weighted average grant fair value (in dollars per share)	$ 9.20
2020 Stock Award and Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available to be granted under plan (in shares)	2,400,000

Share-Based Compensation - Tota

Share-Based Compensation - Total Compensation Cost Recognized for Share-based Awards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Share-based compensation expense	$ 8,874	$ 7,463	$ 7,360
Capitalized share-based compensation	422	503	295
Total share-based compensation	$ 9,296	$ 7,966	$ 7,655

Share-Based Compensation - Assu

Share-Based Compensation - Assumptions Used in the Determination of Grant-Date Fair Value of Awards (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
TSR Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant date market value of a common share	$ 38.26	$ 53.91	$ 36.84
Risk-free interest rate, minimum	385%	120%	24%
Risk-free interest rate, maximum	4.14%	1.68%	0.78%
Dividend yield	4.70%	3.50%	4%
Expected volatility, minimum	2,856%	2,263%	2,308%
Expected volatility, maximum	2,859%	2,483%	2,821%
TSR LTIP Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Derived vesting period of TSR Restricted Stock and TSR LTIP I units	3 years 6 months	3 years 6 months	3 years 2 months 12 days
TSR LTIP II Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average expected term of TSR Stock Options and LTIP II units	5 years 6 months	5 years 4 months 24 days	5 years 4 months 24 days

Income Taxes - Components of In

Income Taxes - Components of Income Tax Benefit or Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ (1,349)	$ (756)	$ 7,409
State	(952)	(2,807)	(1,971)
Total current	(2,301)	(3,563)	5,438
Deferred:
Federal	(102)	(291)	(153)
State	(24)	(69)	(39)
Total deferred	(126)	(360)	(192)
Total (expense) benefit	$ (2,427)	$ (3,923)	$ 5,246

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Consolidated income (loss) subject to tax	$ 7.4	$ 28.9

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Tax Attributable to Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Amount
Tax expense provision at United States statutory rates on consolidated income from continuing operations subject to tax	$ (5,065)	$ (1,554)	$ (6,064)
State income tax expense, net of federal tax expense	(996)	(2,853)	(2,011)
Tax credits	3,420	191	3,508
TRS REIT election	0	0	9,656
Other	214	293	157
Total (expense) benefit	$ (2,427)	$ (3,923)	$ 5,246
Percent
Tax expense provision at United States statutory rates on consolidated income from continuing operations subject to tax	(21.00%)	(21.00%)	(21.00%)
State income tax expense, net of federal tax expense	(4.10%)	(38.60%)	(7.00%)
Tax credits	14.20%	2.60%	12.10%
TRS REIT election	0%	0%	33.40%
Other	0.90%	4%	0.50%
Total income tax expense	(10.00%)	(53.00%)	18%

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of Income Tax Attributable to Operations Footnote (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Contingency [Line Items]
Consolidated income (loss) subject to tax		$ 7,400	$ 28,900
State income tax expense, net of federal tax expense	$ (996)	$ (2,853)	$ (2,011)
Apartment Income REIT, L.P
Income Tax Contingency [Line Items]
Consolidated income (loss) subject to tax	$ 24,100

Income Taxes - Schedule of Divi

Income Taxes - Schedule of Dividends Per Share Held (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Amount
Ordinary income	$ 0.24	$ 0.21	$ 0
Capital gains	0.06	1.37	0.44
Qualified dividends	0	0.03	0
Unrecaptured Section 1250 gain	0	0.19	0.13
Return of capital	1.50	0	1.17
Total	$ 1.80	$ 1.80	$ 1.74
Percentage
Ordinary income	13.10%	11.80%	0%
Capital gains	3.50%	76%	25.30%
Qualified dividends	0%	1.90%	0%
Unrecaptured Section 1250 gain	0%	10.30%	7.50%
Return of capital	83.40%	0%	67.20%
Total	100%	100%	100%

Earnings and Dividends per Sh_3

Earnings and Dividends per Share and per Unit - Reconciliations of the numerator and denominator (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Earnings Per Share and Per Unit [Line Items]
Net income (loss) attributable to AIR common stockholders	$ 634,444	$ 903,642	$ 447,124
Effect of dilutive instruments	6,280	6,388	0
Net (loss) income attributed to AIR common stockholders	$ 640,724	$ 910,030	$ 447,124
Denominator:
Basic weighted-average common shares outstanding	147,899	154,093	154,135
Dilutive common share equivalents outstanding	2,321	2,494	368
Dilutive weighted-average common shares outstanding	150,220	156,587	154,503
Earnings per unit - basic (in dollars per share)	$ 4.29	$ 5.86	$ 2.90
Earnings per unit - diluted (in dollars per share)	$ 4.27	$ 5.81	$ 2.89
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	3,400	0	1,500
Apartment Income REIT, L.P
Schedule of Earnings Per Share and Per Unit [Line Items]
Net income (loss) attributable to AIR common stockholders	$ 677,165	$ 962,414	$ 475,557
Effect of dilutive instruments	6,280	6,388	0
Net (loss) income attributed to AIR common stockholders	$ 683,445	$ 968,802	$ 475,557
Denominator:
Basic weighted-average common shares outstanding	157,687	164,141	162,739
Dilutive common share equivalents outstanding	2,321	2,494	369
Dilutive weighted-average common shares outstanding	160,008	166,635	163,108
Earnings per unit - basic (in dollars per share)	$ 4.29	$ 5.86	$ 2.92
Earnings per unit - diluted (in dollars per share)	$ 4.27	$ 5.81	$ 2.92

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Fair Value for Interest Rate Options and swaps (Details) - Fair value recurring - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Interest rate option
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	$ 0	$ 53,481
Interest rate swaps - pay-fixed, receive floating
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	14,679	32,222
Interest rate swaps - pay-floating, receive fixed
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	465	0
Interest rate swap - forward starting
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	331	0
Treasury rate locks
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	319
Level 1 | Interest rate option
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 1 | Interest rate swaps - pay-fixed, receive floating
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 1 | Interest rate swaps - pay-floating, receive fixed
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 1 | Interest rate swap - forward starting
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 1 | Treasury rate locks
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 2 | Interest rate option
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	53,481
Level 2 | Interest rate swaps - pay-fixed, receive floating
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	14,679	32,222
Level 2 | Interest rate swaps - pay-floating, receive fixed
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	465	0
Level 2 | Interest rate swap - forward starting
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	331	0
Level 2 | Treasury rate locks
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	319
Level 3 | Interest rate option
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 3 | Interest rate swaps - pay-fixed, receive floating
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 3 | Interest rate swaps - pay-floating, receive fixed
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 3 | Interest rate swap - forward starting
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	0
Level 3 | Treasury rate locks
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	$ 0	$ 0

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Carrying Value and Fair Value of Non-recourse Property Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long term debt	$ 3,641,629	$ 3,210,344
Preferred equity investment	$ 158,726	0
Derivative, average variable interest rate	4.50%
Receivables with imputed interest, amortization amount	$ 8,500	$ 5,900
Investment interest rate		7.25%
New England
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Partial consider selling value	40,000
Seller financing note receivable, net | Fair value Non-recurring | Carrying Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Seller financing note receivable, net	31,611	$ 32,459
Seller financing note receivable, net | Fair value Non-recurring | Fair Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Seller financing note receivable, net	32,286	33,042
Preferred equity investment | Fair value Non-recurring | Carrying Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Preferred equity investment	0	22,693
Preferred equity investment | Fair value Non-recurring | Fair Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Preferred equity investment	0	23,562
Non-recourse property debt | Fair value Non-recurring | Carrying Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long term debt	1,994,651	2,236,975
Non-recourse property debt | Fair value Non-recurring | Fair Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long term debt	1,753,222	2,001,532
Unsecured notes payable | Fair value Non-recurring | Carrying Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long term debt	400,000	400,000
Unsecured notes payable | Fair value Non-recurring | Fair Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long term debt	$ 371,368	$ 384,244

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Provision for real estate impairment loss	$ 0	$ 0	$ 0
Other Real Estate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Provision for real estate impairment loss	$ 23,600,000	$ 0	$ 0

Derivative Financial Instrume_3

Derivative Financial Instruments and Hedging Activities - Narrative (Details) $ in Thousands	2 Months Ended	3 Months Ended			12 Months Ended
	Feb. 15, 2024 USD ($) apartment	Dec. 31, 2023 USD ($) instrument	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) instrument	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Apr. 23, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification of interest rate derivative (gain) loss to net income (loss)					$ 25,823	$ (273)	$ 0
Derivative, fair value hedge, included in effectiveness, gain (loss)			$ 11,500
Cash flow hedge gain (loss) to be reclassified within 12 months					6,700
Unrealized loss on derivative instruments					16,700
Derivative, change in hedging designation				$ 830,000
Derivative, change in hedging designation, unrealized gains				$ 29,500
Proceeds from termination of derivative instrument					$ 15,500
Derivative, term of contract					2 years 9 months 18 days
Debt, weighted average interest rate								4.60%
Term Loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Proceeds from lines of credit		$ 475,000
Debt instrument, interest rate, stated percentage		4.30%			4.30%
Interest Rate Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash flow hedge gain (loss) to be reclassified within 12 months					$ 13,800
Interest rate swap - forward starting | Fully Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate derivatives terminated | instrument					8
Interest rate swap - forward starting | Partially Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate derivatives terminated | instrument					2
Interest rate swap, pay-floating, receive-fixed | Fully Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate derivatives terminated | instrument					4
Interest rate swap, pay-floating, receive-fixed | Partially Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate derivatives terminated | instrument					1
Interest rate swap, pay-fixed, receive-floating
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount		$ 125,000			$ 125,000
Interest rate swap, pay-fixed, receive-floating | Subsequent Event
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loan term	2 years 2 months 12 days
Number of Instruments | apartment	3
Debt, weighted average interest rate	4.90%
Interest rate swap, pay-fixed, receive-floating | Fully Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate derivatives terminated | instrument					4
Interest rate swap, pay-fixed, receive-floating | Partially Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate derivatives terminated | instrument					1
Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification of interest rate derivative (gain) loss to net income (loss)					$ 4,200	$ 300
Designated as Hedging Instrument | Interest Rate Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification of interest rate derivative (gain) loss to net income (loss)					(25,800)
Not Designated as Hedging Instrument | Interest rate swap, pay-floating, receive-fixed | Fully Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount		330,000			330,000
Not Designated as Hedging Instrument | Interest rate swap, pay-floating, receive-fixed | Partially Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount		100,000			100,000
Not Designated as Hedging Instrument | Interest rate swap, pay-fixed, receive-floating | Subsequent Event
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount	$ 200,000
Not Designated as Hedging Instrument | Interest rate swap, pay-fixed, receive-floating | Fully Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount		330,000			330,000
Not Designated as Hedging Instrument | Interest rate swap, pay-fixed, receive-floating | Partially Terminated
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount		100,000			100,000
Not Designated as Hedging Instrument | Interest rate swap, forward starting
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate Notional Amount		$ 50,000			$ 50,000
Number of Instruments | instrument		1			1

Derivative Financial Instrume_4

Derivative Financial Instruments and Hedging Activities - Schedule of Balance Sheet Hedges (Details) $ in Thousands	Dec. 31, 2023 USD ($) instrument	Dec. 31, 2022 USD ($) instrument
Interest rate swaps - pay-fixed, receive floating | Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments | instrument	7
Aggregate Notional Amount	$ 555,000
Interest rate swaps - pay-fixed, receive floating | Not Designated as Hedging Instrument | Derivative Assets (included in Other Assets, net)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Assets (included in Other Assets, net)	15,266
Interest rate swaps - pay-fixed, receive floating | Not Designated as Hedging Instrument | Derivative Liabilities (included in Accrued Liabilities and Other)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liabilities (included in Accrued Liabilities and Other)	$ (587)
Interest rate swaps - pay-fixed, receive floating | Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments | instrument		10
Aggregate Notional Amount		$ 830,000
Interest rate swaps - pay-fixed, receive floating | Designated as Hedging Instrument | Derivative Assets (included in Other Assets, net)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Assets (included in Other Assets, net)		32,222
Interest rate swaps - pay-fixed, receive floating | Designated as Hedging Instrument | Derivative Liabilities (included in Accrued Liabilities and Other)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liabilities (included in Accrued Liabilities and Other)		$ 0
Interest rate swaps - pay-floating, receive fixed | Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments | instrument	2
Aggregate Notional Amount	$ 80,000
Interest rate swaps - pay-floating, receive fixed | Not Designated as Hedging Instrument | Derivative Assets (included in Other Assets, net)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Assets (included in Other Assets, net)	472
Interest rate swaps - pay-floating, receive fixed | Not Designated as Hedging Instrument | Derivative Liabilities (included in Accrued Liabilities and Other)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liabilities (included in Accrued Liabilities and Other)	$ (7)
Interest rate swap, forward starting | Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments | instrument	1
Aggregate Notional Amount	$ 50,000
Interest rate swap, forward starting | Not Designated as Hedging Instrument | Derivative Assets (included in Other Assets, net)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Assets (included in Other Assets, net)	331
Interest rate swap, forward starting | Not Designated as Hedging Instrument | Derivative Liabilities (included in Accrued Liabilities and Other)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liabilities (included in Accrued Liabilities and Other)	$ 0
Treasury rate locks | Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments | instrument		1
Aggregate Notional Amount		$ 100,000
Treasury rate locks | Designated as Hedging Instrument | Derivative Assets (included in Other Assets, net)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Assets (included in Other Assets, net)		319
Treasury rate locks | Designated as Hedging Instrument | Derivative Liabilities (included in Accrued Liabilities and Other)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liabilities (included in Accrued Liabilities and Other)		$ 0

Variable Interest Entities - Sc

Variable Interest Entities - Schedule of VIEs Consolidated by the AIR Operating Partnership (Details)	12 Months Ended
	Dec. 31, 2023 home apartment	Dec. 31, 2022 apartment
Variable Interest Entity [Line Items]
Apartment units	20,886
Joint Venture Partner
Variable Interest Entity [Line Items]
Number of apartment communities | home	175
Apartment units	328
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
VIEs with interests in apartment communities	3	5
Number of apartment communities	14	16
Apartment units	4,866	5,369
Equity method investment, ownership interest sold	47%

Variable Interest Entities - As

Variable Interest Entities - Assets and Liabilities of VIEs (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Net real estate	$ 5,364,978	$ 5,626,511
Cash and cash equivalents	91,401	95,797
Restricted cash	26,090	205,608
Other assets, net	283,920	549,821
LIABILITIES:
Non-recourse property debt, net	2,223,791	1,985,430
Accrued liabilities and other	296,894	513,805
Variable Interest Entity, Primary Beneficiary
ASSETS
Net real estate	1,013,770	1,066,482
Cash and cash equivalents	41,219	54,319
Restricted cash	2,179	2,378
Other assets, net	22,546	20,944
LIABILITIES:
Non-recourse property debt, net	1,196,280	1,212,065
Accrued liabilities and other	$ 34,903	$ 35,365

Variable Interest Entities - Na

Variable Interest Entities - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Mezzanine investment	$ 0	$ 158,726
Parkmerced Investment
Variable Interest Entity [Line Items]
Mezzanine investment	$ 0	$ 158,700

Business Segments - Narrative (

Business Segments - Narrative (Details)	12 Months Ended
	Dec. 31, 2023 property apartment Segment	Dec. 31, 2022 property
Business Segments (Textual) [Abstract]
Number of reportable segments | Segment	2
Apartment units | apartment	20,886
Other Real Estate
Business Segments (Textual) [Abstract]
Number of apartment communities sold	12
Apartment units | apartment	3,832
Expect To Sell Or Lease To Third Party
Business Segments (Textual) [Abstract]
Number of apartment communities sold	4
Same Store
Business Segments (Textual) [Abstract]
Number of apartment communities sold	63
Apartment units | apartment	22,794
Whole Owned Consolidated Properties | Other Real Estate
Business Segments (Textual) [Abstract]
Number of apartment communities sold	4	4

Business Segments - Summary of

Business Segments - Summary of Information for Reportable Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Summary information for the reportable segments
Total revenues	$ 820,036	$ 773,723	$ 740,853
Other operating expenses not allocated to segments	393,976	384,957	365,547
Total operating expenses	669,808	646,221	633,648
Proportionate property net operating income (loss)	150,228	127,502	107,205
Other items included in income before income tax expense	541,486	846,471	366,773
Income before income tax expense	691,714	973,973	473,978
Real Estate
Summary information for the reportable segments
Property management and operating expenses	275,832	261,264	268,101
Segment Reconciling Items
Summary information for the reportable segments
Total revenues	85,825	125,800	113,634
Other operating expenses not allocated to segments	0	0	0
Total operating expenses	44,295	51,350	48,101
Proportionate property net operating income (loss)	41,530	74,450	65,533
Other items included in income before income tax expense	0	0	0
Income before income tax expense	41,530	74,450	65,533
Segment Reconciling Items | Real Estate
Summary information for the reportable segments
Property management and operating expenses	44,295	51,350	48,101
Corporate Non-Segment
Summary information for the reportable segments
Total revenues	14,482	53,822	127,323
Other operating expenses not allocated to segments	393,976	384,957	365,547
Total operating expenses	434,716	435,388	444,718
Proportionate property net operating income (loss)	(420,234)	(381,566)	(317,395)
Other items included in income before income tax expense	541,486	846,471	366,773
Income before income tax expense	121,252	464,905	49,378
Corporate Non-Segment | Real Estate
Summary information for the reportable segments
Property management and operating expenses	40,740	50,431	79,171
Same Store | Operating Segments
Summary information for the reportable segments
Total revenues	600,142	556,318	499,896
Other operating expenses not allocated to segments	0	0	0
Total operating expenses	152,898	147,084	140,829
Proportionate property net operating income (loss)	447,244	409,234	359,067
Other items included in income before income tax expense	0	0	0
Income before income tax expense	447,244	409,234	359,067
Same Store | Operating Segments | Real Estate
Summary information for the reportable segments
Property management and operating expenses	152,898	147,084	140,829
Other Real Estate | Operating Segments
Summary information for the reportable segments
Total revenues	119,587	37,783	0
Other operating expenses not allocated to segments	0	0	0
Total operating expenses	37,899	12,399	0
Proportionate property net operating income (loss)	81,688	25,384	0
Other items included in income before income tax expense	0	0	0
Income before income tax expense	81,688	25,384	0
Other Real Estate | Operating Segments | Real Estate
Summary information for the reportable segments
Property management and operating expenses	$ 37,899	$ 12,399	$ 0

Business Segments - Reconciliat

Business Segments - Reconciliation of Assets from Segment to Consolidated (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Total consolidated assets	$ 6,134,752	$ 6,551,883
Corporate Non-Segment
Segment Reporting Information [Line Items]
Total consolidated assets	484,387	730,391
Same Store | Operating Segments
Segment Reporting Information [Line Items]
Total consolidated assets	4,131,039	4,610,356
Other Real Estate | Operating Segments
Segment Reporting Information [Line Items]
Total consolidated assets	$ 1,519,326	$ 1,211,136

Business Segments - Capital Add

Business Segments - Capital Additions Related to Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total capital additions	$ 155,574	$ 149,706	$ 130,207
Same Store
Segment Reporting Information [Line Items]
Total capital additions	134,850	145,881	130,207
Other Real Estate
Segment Reporting Information [Line Items]
Total capital additions	$ 20,724	$ 3,825	$ 0

Schedule III_ Real Estate and_2

Schedule III: Real Estate and Accumulated Depreciation - Schedule of Real Estate and Accumulated Depreciation (Details) $ in Thousands	Dec. 31, 2023 USD ($) apartment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	20,886
Initial Cost, Land	$ 1,375,186
Initial Cost, Buildings and Improvements	4,064,662
Costs Capitalized Subsequent to Consolidation	2,170,722
Land	1,285,710
Buildings and Improvements	6,324,857
Total	7,610,567	$ 8,076,394	$ 6,885,081	$ 7,468,864
Accumulated Depreciation (AD)	(2,245,589)	$ (2,449,883)	$ (2,284,793)	$ (2,455,505)
Total Cost Net of Accumulated Depreciation	5,364,978
Encumbrances	$ 2,236,975
Other Real Estate
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	3,331
Initial Cost, Land	$ 311,577
Initial Cost, Buildings and Improvements	1,415,502
Costs Capitalized Subsequent to Consolidation	37,098
Land	311,574
Buildings and Improvements	1,452,600
Total	1,764,174
Accumulated Depreciation (AD)	(72,510)
Total Cost Net of Accumulated Depreciation	1,691,664
Encumbrances	$ 166,399
Other Real Estate | 707 Leahy
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	110
Initial Cost, Land	$ 20,956
Initial Cost, Buildings and Improvements	62,605
Costs Capitalized Subsequent to Consolidation	185
Land	20,956
Buildings and Improvements	62,790
Total	83,746
Accumulated Depreciation (AD)	(3,069)
Total Cost Net of Accumulated Depreciation	80,677
Encumbrances	$ 0
Other Real Estate | The Reserve at Coconut Point
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	180
Initial Cost, Land	$ 5,162
Initial Cost, Buildings and Improvements	66,593
Costs Capitalized Subsequent to Consolidation	237
Land	5,162
Buildings and Improvements	66,830
Total	71,992
Accumulated Depreciation (AD)	(4,732)
Total Cost Net of Accumulated Depreciation	67,260
Encumbrances	$ 0
Other Real Estate | District at Flagler Village, The
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	350
Initial Cost, Land	$ 14,472
Initial Cost, Buildings and Improvements	156,718
Costs Capitalized Subsequent to Consolidation	1,526
Land	14,472
Buildings and Improvements	158,244
Total	172,716
Accumulated Depreciation (AD)	(8,721)
Total Cost Net of Accumulated Depreciation	163,995
Encumbrances	$ 0
Other Real Estate | Flamingo Point, North Tower
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	366
Initial Cost, Land	$ 91,529
Initial Cost, Buildings and Improvements	290,682
Costs Capitalized Subsequent to Consolidation	1,561
Land	91,529
Buildings and Improvements	292,243
Total	383,772
Accumulated Depreciation (AD)	(13,602)
Total Cost Net of Accumulated Depreciation	370,170
Encumbrances	$ 0
Other Real Estate | Fremont
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	253
Initial Cost, Land	$ 7,218
Initial Cost, Buildings and Improvements	92,621
Costs Capitalized Subsequent to Consolidation	213
Land	7,218
Buildings and Improvements	92,834
Total	100,052
Accumulated Depreciation (AD)	(4,651)
Total Cost Net of Accumulated Depreciation	95,401
Encumbrances	0
Other Real Estate | Merrill House
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Initial Cost, Land	13,768
Initial Cost, Buildings and Improvements	74,541
Costs Capitalized Subsequent to Consolidation	$ 572
Other Real Estate | Prism
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	136
Land	$ 13,768
Buildings and Improvements	75,113
Total	88,881
Accumulated Depreciation (AD)	(3,668)
Total Cost Net of Accumulated Depreciation	85,213
Encumbrances	$ 0
Other Real Estate | Willard Towers
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	525
Initial Cost, Land	$ 334
Initial Cost, Buildings and Improvements	179,141
Costs Capitalized Subsequent to Consolidation	12,701
Land	334
Buildings and Improvements	191,842
Total	192,176
Accumulated Depreciation (AD)	(10,776)
Total Cost Net of Accumulated Depreciation	181,400
Encumbrances	$ 0
Other Real Estate | Watermarc at Biscayne Bay, The
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	296
Initial Cost, Land	$ 34,710
Initial Cost, Buildings and Improvements	174,237
Costs Capitalized Subsequent to Consolidation	2,531
Land	34,710
Buildings and Improvements	176,768
Total	211,478
Accumulated Depreciation (AD)	(10,271)
Total Cost Net of Accumulated Depreciation	201,207
Encumbrances	0
Other Real Estate | Other
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Initial Cost, Land	4,863
Initial Cost, Buildings and Improvements	0
Costs Capitalized Subsequent to Consolidation	12,590
Land	4,860
Buildings and Improvements	12,590
Total	17,450
Accumulated Depreciation (AD)	(4,183)
Total Cost Net of Accumulated Depreciation	13,267
Encumbrances	$ 7,537
Other Real Estate | Brizo Apartments
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	260
Initial Cost, Land	$ 7,652
Initial Cost, Buildings and Improvements	60,170
Costs Capitalized Subsequent to Consolidation	1,055
Land	7,652
Buildings and Improvements	61,225
Total	68,877
Accumulated Depreciation (AD)	(738)
Total Cost Net of Accumulated Depreciation	68,139
Encumbrances	$ 41,026
Other Real Estate | Southgate Towers
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	495
Initial Cost, Land	$ 99,338
Initial Cost, Buildings and Improvements	187,427
Costs Capitalized Subsequent to Consolidation	3,392
Land	99,338
Buildings and Improvements	190,819
Total	290,157
Accumulated Depreciation (AD)	(6,855)
Total Cost Net of Accumulated Depreciation	283,302
Encumbrances	$ 84,336
Other Real Estate | Villages at Old Towne
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	360
Initial Cost, Land	$ 11,575
Initial Cost, Buildings and Improvements	70,767
Costs Capitalized Subsequent to Consolidation	535
Land	11,575
Buildings and Improvements	71,302
Total	82,877
Accumulated Depreciation (AD)	(1,244)
Total Cost Net of Accumulated Depreciation	81,633
Encumbrances	$ 33,500
Same Store Sales
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	17,555
Initial Cost, Land	$ 1,063,609
Initial Cost, Buildings and Improvements	2,649,160
Costs Capitalized Subsequent to Consolidation	2,133,624
Land	974,136
Buildings and Improvements	4,872,257
Total	5,846,393
Accumulated Depreciation (AD)	(2,173,079)
Total Cost Net of Accumulated Depreciation	3,673,314
Encumbrances	$ 2,070,576
Same Store Sales | 21 Fitzsimons
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	601
Initial Cost, Land	$ 13,176
Initial Cost, Buildings and Improvements	110,795
Costs Capitalized Subsequent to Consolidation	40,086
Land	13,176
Buildings and Improvements	150,881
Total	164,057
Accumulated Depreciation (AD)	(53,485)
Total Cost Net of Accumulated Depreciation	110,572
Encumbrances	$ 81,838
Same Store Sales | 3400 Avenue of the Arts
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	770
Initial Cost, Land	$ 57,241
Initial Cost, Buildings and Improvements	65,506
Costs Capitalized Subsequent to Consolidation	101,943
Land	57,241
Buildings and Improvements	167,449
Total	224,690
Accumulated Depreciation (AD)	(116,299)
Total Cost Net of Accumulated Depreciation	108,391
Encumbrances	$ 0
Same Store Sales | 777 South Broad Street
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	146
Initial Cost, Land	$ 6,986
Initial Cost, Buildings and Improvements	67,512
Costs Capitalized Subsequent to Consolidation	5,229
Land	6,986
Buildings and Improvements	72,741
Total	79,727
Accumulated Depreciation (AD)	(16,149)
Total Cost Net of Accumulated Depreciation	63,578
Encumbrances	$ 37,051
Same Store Sales | Axiom
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	115
Initial Cost, Land	$ 0
Initial Cost, Buildings and Improvements	63,612
Costs Capitalized Subsequent to Consolidation	5,133
Land	0
Buildings and Improvements	68,745
Total	68,745
Accumulated Depreciation (AD)	(21,542)
Total Cost Net of Accumulated Depreciation	47,203
Encumbrances	$ 0
Same Store Sales | Bay Parc Plaza
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	474
Initial Cost, Land	$ 22,680
Initial Cost, Buildings and Improvements	41,847
Costs Capitalized Subsequent to Consolidation	65,092
Land	22,680
Buildings and Improvements	106,939
Total	129,619
Accumulated Depreciation (AD)	(43,586)
Total Cost Net of Accumulated Depreciation	86,033
Encumbrances	$ 69,987
Same Store Sales | Boulder Creek
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	221
Initial Cost, Land	$ 754
Initial Cost, Buildings and Improvements	7,730
Costs Capitalized Subsequent to Consolidation	19,634
Land	754
Buildings and Improvements	27,364
Total	28,118
Accumulated Depreciation (AD)	(21,125)
Total Cost Net of Accumulated Depreciation	6,993
Encumbrances	$ 0
Same Store Sales | Broadcast Center
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	279
Initial Cost, Land	$ 29,407
Initial Cost, Buildings and Improvements	41,244
Costs Capitalized Subsequent to Consolidation	44,820
Land	29,407
Buildings and Improvements	86,064
Total	115,471
Accumulated Depreciation (AD)	(46,287)
Total Cost Net of Accumulated Depreciation	69,184
Encumbrances	$ 0
Same Store Sales | Calhoun Beach Club
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	332
Initial Cost, Land	$ 11,708
Initial Cost, Buildings and Improvements	73,334
Costs Capitalized Subsequent to Consolidation	62,140
Land	11,708
Buildings and Improvements	135,474
Total	147,182
Accumulated Depreciation (AD)	(101,407)
Total Cost Net of Accumulated Depreciation	45,775
Encumbrances	$ 0
Same Store Sales | Charlesbank Apartment Homes
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	44
Initial Cost, Land	$ 3,399
Initial Cost, Buildings and Improvements	11,726
Costs Capitalized Subsequent to Consolidation	1,720
Land	3,399
Buildings and Improvements	13,446
Total	16,845
Accumulated Depreciation (AD)	(4,902)
Total Cost Net of Accumulated Depreciation	11,943
Encumbrances	$ 0
Same Store Sales | Chestnut Hall
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	315
Initial Cost, Land	$ 12,338
Initial Cost, Buildings and Improvements	14,299
Costs Capitalized Subsequent to Consolidation	14,895
Land	12,338
Buildings and Improvements	29,194
Total	41,532
Accumulated Depreciation (AD)	(16,044)
Total Cost Net of Accumulated Depreciation	25,488
Encumbrances	$ 32,291
Same Store Sales | Flamingo Point, Center Tower
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	513
Initial Cost, Land	$ 15,279
Initial Cost, Buildings and Improvements	29,358
Costs Capitalized Subsequent to Consolidation	240,993
Land	15,279
Buildings and Improvements	270,351
Total	285,630
Accumulated Depreciation (AD)	(146,577)
Total Cost Net of Accumulated Depreciation	139,053
Encumbrances	$ 0
Same Store Sales | Flamingo Point, South Tower
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	260
Initial Cost, Land	$ 0
Initial Cost, Buildings and Improvements	14,570
Costs Capitalized Subsequent to Consolidation	74,656
Land	0
Buildings and Improvements	89,226
Total	89,226
Accumulated Depreciation (AD)	(21,537)
Total Cost Net of Accumulated Depreciation	67,689
Encumbrances	$ 0
Same Store Sales | Foxchase
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	2,113
Initial Cost, Land	$ 15,496
Initial Cost, Buildings and Improvements	96,062
Costs Capitalized Subsequent to Consolidation	95,399
Land	15,496
Buildings and Improvements	191,461
Total	206,957
Accumulated Depreciation (AD)	(127,305)
Total Cost Net of Accumulated Depreciation	79,652
Encumbrances	$ 170,000
Same Store Sales | Hidden Cove
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	334
Initial Cost, Land	$ 3,043
Initial Cost, Buildings and Improvements	17,616
Costs Capitalized Subsequent to Consolidation	20,372
Land	3,043
Buildings and Improvements	37,988
Total	41,031
Accumulated Depreciation (AD)	(23,334)
Total Cost Net of Accumulated Depreciation	17,697
Encumbrances	$ 64,757
Same Store Sales | Hidden Cove II
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	118
Initial Cost, Land	$ 12,849
Initial Cost, Buildings and Improvements	6,530
Costs Capitalized Subsequent to Consolidation	7,518
Land	12,849
Buildings and Improvements	14,048
Total	26,897
Accumulated Depreciation (AD)	(7,867)
Total Cost Net of Accumulated Depreciation	19,030
Encumbrances	$ 25,183
Same Store Sales | Hillcreste
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	315
Initial Cost, Land	$ 35,862
Initial Cost, Buildings and Improvements	47,216
Costs Capitalized Subsequent to Consolidation	26,720
Land	35,862
Buildings and Improvements	73,936
Total	109,798
Accumulated Depreciation (AD)	(41,057)
Total Cost Net of Accumulated Depreciation	68,741
Encumbrances	$ 0
Same Store Sales | Indian Oaks
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	254
Initial Cost, Land	$ 24,523
Initial Cost, Buildings and Improvements	15,801
Costs Capitalized Subsequent to Consolidation	13,395
Land	24,523
Buildings and Improvements	29,196
Total	53,719
Accumulated Depreciation (AD)	(21,548)
Total Cost Net of Accumulated Depreciation	32,171
Encumbrances	$ 58,955
Same Store Sales | Indigo Apartment Homes
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	463
Initial Cost, Land	$ 26,932
Initial Cost, Buildings and Improvements	296,116
Costs Capitalized Subsequent to Consolidation	12,194
Land	26,932
Buildings and Improvements	308,310
Total	335,242
Accumulated Depreciation (AD)	(80,869)
Total Cost Net of Accumulated Depreciation	254,373
Encumbrances	$ 171,938
Same Store Sales | Laurel Crossing
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	418
Initial Cost, Land	$ 49,474
Initial Cost, Buildings and Improvements	17,756
Costs Capitalized Subsequent to Consolidation	20,756
Land	49,474
Buildings and Improvements	38,512
Total	87,986
Accumulated Depreciation (AD)	(22,212)
Total Cost Net of Accumulated Depreciation	65,774
Encumbrances	$ 0
Same Store Sales | Lincoln Place
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	795
Initial Cost, Land	$ 128,332
Initial Cost, Buildings and Improvements	10,439
Costs Capitalized Subsequent to Consolidation	256,641
Land	44,198
Buildings and Improvements	351,214
Total	395,412
Accumulated Depreciation (AD)	(193,540)
Total Cost Net of Accumulated Depreciation	201,872
Encumbrances	$ 169,960
Same Store Sales | Malibu Canyon
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	698
Initial Cost, Land	$ 69,834
Initial Cost, Buildings and Improvements	53,438
Costs Capitalized Subsequent to Consolidation	45,720
Land	69,834
Buildings and Improvements	99,158
Total	168,992
Accumulated Depreciation (AD)	(70,914)
Total Cost Net of Accumulated Depreciation	98,078
Encumbrances	$ 158,950
Same Store Sales | Mariners Cove
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	500
Initial Cost, Land	$ 0
Initial Cost, Buildings and Improvements	66,861
Costs Capitalized Subsequent to Consolidation	18,641
Land	0
Buildings and Improvements	85,502
Total	85,502
Accumulated Depreciation (AD)	(52,801)
Total Cost Net of Accumulated Depreciation	32,701
Encumbrances	$ 0
Same Store Sales | Meadow Creek
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	332
Initial Cost, Land	$ 1,435
Initial Cost, Buildings and Improvements	24,533
Costs Capitalized Subsequent to Consolidation	13,660
Land	1,435
Buildings and Improvements	38,193
Total	39,628
Accumulated Depreciation (AD)	(27,091)
Total Cost Net of Accumulated Depreciation	12,537
Encumbrances	$ 0
Same Store Sales | Mezzo
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	95
Initial Cost, Land	$ 4,292
Initial Cost, Buildings and Improvements	34,178
Costs Capitalized Subsequent to Consolidation	3,616
Land	4,292
Buildings and Improvements	37,794
Total	42,086
Accumulated Depreciation (AD)	(12,332)
Total Cost Net of Accumulated Depreciation	29,754
Encumbrances	$ 0
Same Store Sales | Monterey Grove
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	224
Initial Cost, Land	$ 34,325
Initial Cost, Buildings and Improvements	21,939
Costs Capitalized Subsequent to Consolidation	19,497
Land	34,325
Buildings and Improvements	41,436
Total	75,761
Accumulated Depreciation (AD)	(20,533)
Total Cost Net of Accumulated Depreciation	55,228
Encumbrances	$ 45,541
Same Store Sales | Ocean House and on into Prospect
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	53
Initial Cost, Land	$ 12,528
Initial Cost, Buildings and Improvements	18,805
Costs Capitalized Subsequent to Consolidation	17,298
Land	12,528
Buildings and Improvements	36,103
Total	48,631
Accumulated Depreciation (AD)	(15,618)
Total Cost Net of Accumulated Depreciation	33,013
Encumbrances	$ 0
Same Store Sales | One Ardmore
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	110
Initial Cost, Land	$ 4,929
Initial Cost, Buildings and Improvements	61,631
Costs Capitalized Subsequent to Consolidation	4,135
Land	4,929
Buildings and Improvements	65,766
Total	70,695
Accumulated Depreciation (AD)	(11,520)
Total Cost Net of Accumulated Depreciation	59,175
Encumbrances	$ 28,504
Same Store Sales | One Canal
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	310
Initial Cost, Land	$ 0
Initial Cost, Buildings and Improvements	15,873
Costs Capitalized Subsequent to Consolidation	184,077
Land	0
Buildings and Improvements	199,950
Total	199,950
Accumulated Depreciation (AD)	(59,287)
Total Cost Net of Accumulated Depreciation	140,663
Encumbrances	$ 0
Same Store Sales | Pacific Bay Vistas
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	308
Initial Cost, Land	$ 28,694
Initial Cost, Buildings and Improvements	62,460
Costs Capitalized Subsequent to Consolidation	34,167
Land	23,354
Buildings and Improvements	101,967
Total	125,321
Accumulated Depreciation (AD)	(51,306)
Total Cost Net of Accumulated Depreciation	74,015
Encumbrances	$ 95,804
Same Store Sales | Pacifica Park
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	104
Initial Cost, Land	$ 12,970
Initial Cost, Buildings and Improvements	6,579
Costs Capitalized Subsequent to Consolidation	9,765
Land	12,970
Buildings and Improvements	16,344
Total	29,314
Accumulated Depreciation (AD)	(10,197)
Total Cost Net of Accumulated Depreciation	19,117
Encumbrances	$ 37,264
Same Store Sales | Palazzo at Park La Brea, The
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	521
Initial Cost, Land	$ 48,362
Initial Cost, Buildings and Improvements	125,464
Costs Capitalized Subsequent to Consolidation	61,144
Land	48,362
Buildings and Improvements	186,608
Total	234,970
Accumulated Depreciation (AD)	(111,787)
Total Cost Net of Accumulated Depreciation	123,183
Encumbrances	$ 205,883
Same Store Sales | Palazzo East at Park La Brea, The
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	611
Initial Cost, Land	$ 72,578
Initial Cost, Buildings and Improvements	136,503
Costs Capitalized Subsequent to Consolidation	43,699
Land	72,578
Buildings and Improvements	180,202
Total	252,780
Accumulated Depreciation (AD)	(110,240)
Total Cost Net of Accumulated Depreciation	142,540
Encumbrances	$ 174,531
Same Store Sales | Parc Mosaic
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	226
Initial Cost, Land	$ 15,300
Initial Cost, Buildings and Improvements	0
Costs Capitalized Subsequent to Consolidation	111,319
Land	15,300
Buildings and Improvements	111,319
Total	126,619
Accumulated Depreciation (AD)	(24,893)
Total Cost Net of Accumulated Depreciation	101,726
Encumbrances	$ 0
Same Store Sales | Peachtree Park
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	303
Initial Cost, Land	$ 4,684
Initial Cost, Buildings and Improvements	11,713
Costs Capitalized Subsequent to Consolidation	17,696
Land	4,684
Buildings and Improvements	29,409
Total	34,093
Accumulated Depreciation (AD)	(20,455)
Total Cost Net of Accumulated Depreciation	13,638
Encumbrances	$ 0
Same Store Sales | Preserve at Marin
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	126
Initial Cost, Land	$ 13,516
Initial Cost, Buildings and Improvements	30,132
Costs Capitalized Subsequent to Consolidation	81,922
Land	13,516
Buildings and Improvements	112,054
Total	125,570
Accumulated Depreciation (AD)	(48,841)
Total Cost Net of Accumulated Depreciation	76,729
Encumbrances	$ 0
Same Store Sales | Royal Crest Estates
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	588
Initial Cost, Land	$ 51,292
Initial Cost, Buildings and Improvements	36,808
Costs Capitalized Subsequent to Consolidation	29,995
Land	51,292
Buildings and Improvements	66,803
Total	118,095
Accumulated Depreciation (AD)	(45,758)
Total Cost Net of Accumulated Depreciation	72,337
Encumbrances	$ 0
Same Store Sales | Saybrook Point
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	324
Initial Cost, Land	$ 32,842
Initial Cost, Buildings and Improvements	84,457
Costs Capitalized Subsequent to Consolidation	27,878
Land	32,842
Buildings and Improvements	112,335
Total	145,177
Accumulated Depreciation (AD)	(37,931)
Total Cost Net of Accumulated Depreciation	107,246
Encumbrances	$ 107,347
Same Store Sales | SouthStar Lofts
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	85
Initial Cost, Land	$ 1,780
Initial Cost, Buildings and Improvements	37,428
Costs Capitalized Subsequent to Consolidation	1,458
Land	1,780
Buildings and Improvements	38,886
Total	40,666
Accumulated Depreciation (AD)	(8,261)
Total Cost Net of Accumulated Depreciation	32,405
Encumbrances	$ 17,000
Same Store Sales | Sterling Apartment Homes, The
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	534
Initial Cost, Land	$ 8,871
Initial Cost, Buildings and Improvements	55,365
Costs Capitalized Subsequent to Consolidation	120,985
Land	8,871
Buildings and Improvements	176,350
Total	185,221
Accumulated Depreciation (AD)	(121,690)
Total Cost Net of Accumulated Depreciation	63,531
Encumbrances	$ 0
Same Store Sales | The Left Bank
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	282
Initial Cost, Land	$ 0
Initial Cost, Buildings and Improvements	130,893
Costs Capitalized Subsequent to Consolidation	26,672
Land	0
Buildings and Improvements	157,565
Total	157,565
Accumulated Depreciation (AD)	(34,431)
Total Cost Net of Accumulated Depreciation	123,134
Encumbrances	$ 73,658
Same Store Sales | Tremont
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	78
Initial Cost, Land	$ 5,274
Initial Cost, Buildings and Improvements	18,011
Costs Capitalized Subsequent to Consolidation	4,365
Land	5,274
Buildings and Improvements	22,376
Total	27,650
Accumulated Depreciation (AD)	(7,708)
Total Cost Net of Accumulated Depreciation	19,942
Encumbrances	$ 0
Same Store Sales | Villas at Park La Brea, The
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	250
Initial Cost, Land	$ 8,630
Initial Cost, Buildings and Improvements	48,871
Costs Capitalized Subsequent to Consolidation	24,942
Land	8,630
Buildings and Improvements	73,813
Total	82,443
Accumulated Depreciation (AD)	(46,528)
Total Cost Net of Accumulated Depreciation	35,915
Encumbrances	$ 0
Same Store Sales | Villas of Pasadena
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	92
Initial Cost, Land	$ 9,693
Initial Cost, Buildings and Improvements	6,818
Costs Capitalized Subsequent to Consolidation	5,826
Land	9,693
Buildings and Improvements	12,644
Total	22,337
Accumulated Depreciation (AD)	(7,888)
Total Cost Net of Accumulated Depreciation	14,449
Encumbrances	$ 20,500
Same Store Sales | Vivo
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	91
Initial Cost, Land	$ 6,450
Initial Cost, Buildings and Improvements	35,974
Costs Capitalized Subsequent to Consolidation	6,623
Land	6,450
Buildings and Improvements	42,597
Total	49,047
Accumulated Depreciation (AD)	(19,812)
Total Cost Net of Accumulated Depreciation	29,235
Encumbrances	$ 0
Same Store Sales | Waterways Village
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	180
Initial Cost, Land	$ 4,504
Initial Cost, Buildings and Improvements	11,064
Costs Capitalized Subsequent to Consolidation	19,088
Land	4,504
Buildings and Improvements	30,152
Total	34,656
Accumulated Depreciation (AD)	(19,909)
Total Cost Net of Accumulated Depreciation	14,747
Encumbrances	$ 0
Same Store Sales | City Center on 7th
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	700
Initial Cost, Land	$ 35,196
Initial Cost, Buildings and Improvements	186,823
Costs Capitalized Subsequent to Consolidation	33,250
Land	35,196
Buildings and Improvements	220,073
Total	255,269
Accumulated Depreciation (AD)	(21,858)
Total Cost Net of Accumulated Depreciation	233,411
Encumbrances	$ 0
Same Store Sales | North Park
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	310
Initial Cost, Land	$ 42,900
Initial Cost, Buildings and Improvements	68,090
Costs Capitalized Subsequent to Consolidation	11,492
Land	42,933
Buildings and Improvements	79,549
Total	122,482
Accumulated Depreciation (AD)	(6,726)
Total Cost Net of Accumulated Depreciation	115,756
Encumbrances	$ 73,634
Same Store Sales | Residences at Capital Crescent Trail
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	258
Initial Cost, Land	$ 15,975
Initial Cost, Buildings and Improvements	84,167
Costs Capitalized Subsequent to Consolidation	8,019
Land	15,975
Buildings and Improvements	92,186
Total	108,161
Accumulated Depreciation (AD)	(7,664)
Total Cost Net of Accumulated Depreciation	100,497
Encumbrances	$ 0
Same Store Sales | Vaughan Place
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Number of apartment homes sold | apartment	382
Initial Cost, Land	$ 47,276
Initial Cost, Buildings and Improvements	125,213
Costs Capitalized Subsequent to Consolidation	17,339
Land	47,244
Buildings and Improvements	142,584
Total	189,828
Accumulated Depreciation (AD)	(12,428)
Total Cost Net of Accumulated Depreciation	177,400
Encumbrances	$ 150,000

Schedule III_ Real Estate and_3

Schedule III: Real Estate and Accumulated Depreciation - Schedule of Real Estate and Accumulated Depreciation (Parenthetical) (Details) $ in Billions	Dec. 31, 2023 USD ($)
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Aggregate cost of land and depreciable property for federal income tax purposes	$ 6.9
Minimum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for buildings and improvements	5 years
Maximum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for buildings and improvements	30 years

Schedule III_ Real Estate and_4

Schedule III: Real Estate and Accumulated Depreciation - Summary Real Estate and Accumulated Depreciation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Total portfolio balance at beginning of year	$ 8,076,394	$ 6,885,081	$ 7,468,864
Additions during the year:
Acquisitions and lease cancellation	447,945	1,300,122	723,599
Capital additions	168,248	193,360	168,920
Amounts related to assets held for sale			(253,547)
Dispositions and other	(1,082,020)	(302,169)	(1,222,755)
Total real estate balance at end of year	7,610,567	8,076,394	6,885,081
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation [Roll Forward]
Accumulated depreciation balance at beginning of year	2,449,883	2,284,793	2,455,505
Depreciation	310,952	308,382	298,789
Amounts related to assets held for sale			(107,055)
Dispositions and other	(515,246)	(143,292)	(362,446)
Accumulated depreciation balance at end of year	$ 2,245,589	$ 2,449,883	$ 2,284,793