Apartment Investment and Management (AIV) 10-Q 11 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	May 06, 2020
Document Information [Line Items]
Entity Registrant Name	APARTMENT INVESTMENT & MANAGEMENT CO
Entity Central Index Key	0000922864
Document Type	10-Q
Document Period End Date	Mar. 31, 2020
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Trading Symbol	AIV
Entity File Number	1-13232
Entity Tax Identification Number	84-1259577
Entity Address, State or Province	MD
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 Common Stock, Shares Outstanding		148,864,145
Title of 12(b) Security	Class A Common Stock (Aimco Investment and Management Company)
Security Exchange Name	NYSE
Document Quarterly Report	true
Document Transition Report	false
AIMCO Properties, LP [Member]
Document Information [Line Items]
Entity Registrant Name	AIMCO PROPERTIES LP
Entity Central Index Key	0000926660
Document Type	10-Q
Document Period End Date	Mar. 31, 2020
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity File Number	0-24497
Entity Tax Identification Number	84-1275621
Entity Address, State or Province	DE
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

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
ASSETS
Buildings and improvements	$ 6,967,143	$ 6,868,543
Land	1,869,465	1,869,048
Total real estate	8,836,608	8,737,591
Accumulated depreciation	(2,810,949)	(2,718,284)
Net real estate	6,025,659	6,019,307
Cash and cash equivalents	340,883	142,902
Restricted cash	33,933	34,800
Mezzanine investment	286,472	280,258
Other assets	361,298	351,472
Total assets	7,048,245	6,828,739
LIABILITIES AND EQUITY
Non-recourse property debt, net	4,208,687	4,230,590
Revolving credit facility borrowings	593,845	275,000
Total indebtedness	4,802,532	4,505,590
Accrued liabilities and other	349,099	360,574
Total liabilities	5,151,631	4,866,164
Redeemable preferred OP Units	96,449	97,064
Redeemable noncontrolling interests in consolidated real estate partnership	4,617	4,716
Commitments and contingencies (Note 4)
Equity/Partners' Capital:
Common Stock, $0.01 par value, 510,587,500 shares authorized, 148,700,407 and 148,885,197 shares issued/outstanding at March 31, 2020 and December 31, 2019, respectively	1,487	1,489
Additional paid-in capital	3,488,611	3,497,367
Accumulated other comprehensive income	4,139	4,195
Distributions in excess of earnings	(1,776,782)	(1,722,402)
Total Aimco equity	1,717,455	1,780,649
Noncontrolling interests in consolidated real estate partnerships	(3,409)	(3,296)
Common noncontrolling interests in Aimco Operating Partnership	81,502	83,442
Total equity	1,795,548	1,860,795
Total liabilities and equity	7,048,245	6,828,739
AIMCO Properties, LP [Member]
ASSETS
Buildings and improvements	6,967,143	6,868,543
Land	1,869,465	1,869,048
Total real estate	8,836,608	8,737,591
Accumulated depreciation	(2,810,949)	(2,718,284)
Net real estate	6,025,659	6,019,307
Cash and cash equivalents	340,883	142,902
Restricted cash	33,933	34,800
Mezzanine investment	286,472	280,258
Other assets	361,298	351,472
Total assets	7,048,245	6,828,739
LIABILITIES AND EQUITY
Non-recourse property debt, net	4,208,687	4,230,590
Revolving credit facility borrowings	593,845	275,000
Total indebtedness	4,802,532	4,505,590
Accrued liabilities and other	349,099	360,574
Total liabilities	5,151,631	4,866,164
Redeemable preferred OP Units	96,449	97,064
Redeemable noncontrolling interests in consolidated real estate partnership	4,617	4,716
Commitments and contingencies (Note 4)
Equity/Partners' Capital:
General Partner and Special Limited Partner	1,717,455	1,780,649
Limited Partners	81,502	83,442
Partners’ capital attributable to the Aimco Operating Partnership	1,798,957	1,864,091
Partners' Capital Attributable to Noncontrolling Interest	(3,409)	(3,296)
Total partners’ capital	1,795,548	1,860,795
Total liabilities and equity	$ 7,048,245	$ 6,828,739

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (in shares)	510,587,500	510,587,500
Common Stock, shares issued (in shares)	148,700,407	148,885,197
Common Stock, shares outstanding (in shares)	148,700,407	148,885,197

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
REVENUES
Rental and other property revenues	$ 224,552	$ 230,235
OPERATING EXPENSES
Property operating expenses	75,480	78,959
Depreciation and amortization	100,476	93,565
General and administrative expenses	10,108	9,829
Investment management expenses	1,184	1,332
Other expenses, net	1,642	5,136
Total operating expenses	188,890	188,821
Interest income	4,523	2,726
Interest expense	(41,336)	(41,409)
(Loss) gain on dispositions of real estate	(34)	291,473
Mezzanine / Unconsolidated partnerships investment income, net	6,747	0
Income before income tax benefit (expense)	5,744	294,276
Income tax benefit (expense)	3,233	(2,981)
Net income	8,977	291,295
Noncontrolling interests:
Net income attributable to noncontrolling interests in consolidated real estate partnerships	(18)	(91)
Net income attributable to preferred noncontrolling interests in Aimco Operating Partnership	(1,869)	(1,934)
Net income attributable to common noncontrolling interests in Aimco Operating Partnership	(368)	(15,137)
Net income attributable to noncontrolling interests	(2,255)	(17,162)
Net income attributable to the company	6,722	274,133
Net income attributable to the company's preferred equity holders	0	(2,148)
Net income attributable to participating securities	(43)	(417)
Net income attributable to the company's common equity holders	$ 6,679	$ 271,568
Net income attributable to Aimco per common share – basic and diluted	$ 0.04	$ 1.88
Weighted average common shares/units outstanding - basic	148,518	144,232
Weighted average common shares/units outstanding - diluted	148,786	144,445
AIMCO Properties, LP [Member]
REVENUES
Rental and other property revenues	$ 224,552	$ 230,235
OPERATING EXPENSES
Property operating expenses	75,480	78,959
Depreciation and amortization	100,476	93,565
General and administrative expenses	10,108	9,829
Investment management expenses	1,184	1,332
Other expenses, net	1,642	5,136
Total operating expenses	188,890	188,821
Interest income	4,523	2,726
Interest expense	(41,336)	(41,409)
(Loss) gain on dispositions of real estate	(34)	291,473
Mezzanine / Unconsolidated partnerships investment income, net	6,747	0
Income before income tax benefit (expense)	5,744	294,276
Income tax benefit (expense)	3,233	(2,981)
Net income	8,977	291,295
Noncontrolling interests:
Net income attributable to noncontrolling interests in consolidated real estate partnerships	(18)	(91)
Net income attributable to preferred noncontrolling interests in Aimco Operating Partnership	(1,869)	(4,082)
Net income attributable to the company	8,959	291,204
Net income attributable to participating securities	(43)	(483)
Net income attributable to the company's common equity holders	$ 7,047	$ 286,639
Net income attributable to Aimco per common share – basic and diluted	$ 0.04	$ 1.88
Weighted average common shares/units outstanding - basic	156,660	152,303
Weighted average common shares/units outstanding - diluted	157,003	152,632
Unconsolidated Real Estate Partnerships [Member]
OPERATING EXPENSES
Mezzanine / Unconsolidated partnerships investment income, net	$ 182	$ 72
Unconsolidated Real Estate Partnerships [Member] | AIMCO Properties, LP [Member]
OPERATING EXPENSES
Mezzanine / Unconsolidated partnerships investment income, net	$ 182	$ 72

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net income	$ 8,977	$ 291,295
Unrealized (losses) gains on available for sale debt securities	(60)	61
Comprehensive income	8,917	291,356
Comprehensive income attributable to noncontrolling interests	(2,251)	(17,166)
Comprehensive income attributable to Aimco/Operating Partnership	6,666	274,190
AIMCO Properties, LP [Member]
Net income	8,977	291,295
Unrealized (losses) gains on available for sale debt securities	(60)	61
Comprehensive income	8,917	291,356
Comprehensive income attributable to noncontrolling interests	(18)	(91)
Comprehensive income attributable to Aimco/Operating Partnership	$ 8,899	$ 291,265

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Distributions in Excess of Earnings	Total Aimco Equity	Noncontrolling Interests In Consolidated Real Estate Partnerships	Common Noncontrolling Interests In Aimco Operating Partnership
Balances at Dec. 31, 2018	$ 1,763,641	$ 125,000	$ 1,446	$ 3,515,686	$ 4,794	$ (1,947,507)	$ 1,699,419	$ (2,967)	$ 67,189
Balances (in shares) at Dec. 31, 2018		5,000	144,623
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchases of Common Stock	(20,682)		$ (5)	(20,677)			(20,682)
Repurchases of Common Stock (in shares)			(461)
Redemption of Aimco Operating Partnership units	(2,557)						0	0	(2,557)
Amortization of share-based compensation cost	3,238			2,442			2,442		796
Amortization of share-based compensation cost (in shares)			22
Effect of changes in ownership for consolidated entities				(2,168)			(2,168)		2,168
Change in accumulated other comprehensive income	61				57		57		4
Net income	289,361					274,133	274,133	91	15,137
Common Stock dividends	(67,476)					(67,476)	(67,476)
Common Stock issued to Common Stockholders in special dividend			$ 45	(45)
Common Stock issued to Common Stockholders in special dividend (in shares)			4,492
Preferred Stock dividends	(2,148)					(2,148)	(2,148)
Distributions to noncontrolling interests	(3,244)								(3,244)
Other, net	78		$ 2	57		0	59	19
Other, net (in shares)			82
Balances at Mar. 31, 2019	1,960,272	$ 125,000	$ 1,488	3,495,295	4,851	(1,742,998)	1,883,636	(2,857)	79,493
Balances (in shares) at Mar. 31, 2019		5,000	148,758
Balances at Dec. 31, 2019	1,860,795	$ 0	$ 1,489	3,497,367	4,195	(1,722,402)	1,780,649	(3,296)	83,442
Balances (in shares) at Dec. 31, 2019		0	148,885
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchases of Common Stock	(10,004)	$ 0	$ (2)	(10,002)			(10,004)
Repurchases of Common Stock (in shares)			(234)
Redemption of Aimco Operating Partnership units	(969)							0	(969)
Amortization of share-based compensation cost	2,980			1,929			1,929		1,051
Amortization of share-based compensation cost (in shares)			20
Effect of changes in ownership for consolidated entities	0			(769)			(769)		769
Change in accumulated other comprehensive income	(60)				(56)		(56)		(4)
Net income	7,208					6,722	6,722	118	368
Common Stock dividends	(60,825)					(60,825)	(60,825)
Distributions to noncontrolling interests	(3,228)							(73)	(3,155)
Other, net	(72)			86		0	86	(158)
Other, net (in shares)			29
Balances at Mar. 31, 2020	1,795,548	$ 0	$ 1,487	$ 3,488,611	$ 4,139	(1,776,782)	1,717,455	$ (3,409)	$ 81,502
Balances (in shares) at Mar. 31, 2020		0	148,700
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of a change in accounting principle	$ (277)					$ (277)	$ (277)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 8,977	$ 291,295
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	100,476	93,565
Loss (gain) on dispositions of real estate	34	(291,473)
Income tax (benefit) expense	(3,233)	2,981
Other adjustments	3,157	3,201
Net changes in operating assets and operating liabilities	(31,995)	(17,952)
Net cash provided by operating activities	77,416	81,617
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of real estate and deposits related to purchases of real estate	(2,733)	(2,236)
Capital expenditures	(94,842)	(85,546)
Proceeds from dispositions of real estate	0	342,083
Purchases of corporate assets	(5,104)	(3,319)
Other investing activities	4,665	1,422
Net cash (used in) provided by investing activities	(98,014)	252,404
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal repayments on non-recourse property debt	(22,622)	(19,580)
Net borrowings on (repayments of) revolving credit facility	318,845	(90,360)
Repurchases of Common Stock	(10,004)	(20,682)
Payment of dividends to holders of Preferred Stock	0	(2,148)
Payment of dividends to holders of Common Stock	(61,116)	(67,405)
Payment of distributions to noncontrolling interests	(5,442)	(5,701)
Redemptions of noncontrolling interests in the Aimco Operating Partnership	(1,584)	(2,653)
Other financing activities	(365)	302
Net cash provided by (used in) financing activities	217,712	(208,227)
NET INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	197,114	125,794
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	177,702	72,595
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	374,816	198,389
AIMCO Properties, LP [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	8,977	291,295
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	100,476	93,565
Loss (gain) on dispositions of real estate	34	(291,473)
Income tax (benefit) expense	(3,233)	2,981
Other adjustments	3,157	3,201
Net changes in operating assets and operating liabilities	(31,995)	(17,952)
Net cash provided by operating activities	77,416	81,617
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of real estate and deposits related to purchases of real estate	(2,733)	(2,236)
Capital expenditures	(94,842)	(85,546)
Proceeds from dispositions of real estate	0	342,083
Purchases of corporate assets	(5,104)	(3,319)
Other investing activities	4,665	1,422
Net cash (used in) provided by investing activities	(98,014)	252,404
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal repayments on non-recourse property debt	(22,622)	(19,580)
Net borrowings on (repayments of) revolving credit facility	318,845	(90,360)
Repurchases of Common Stock	(10,004)	(20,682)
Payment of distributions to General Partner and Special Limited Partner	(61,116)	(67,405)
Payment of distributions to Limited Partners	(3,492)	(3,767)
Payment of dividends to holders of Preferred Stock	(1,869)	(4,082)
Payment of distributions to noncontrolling interests	(81)	0
Redemption of common and preferred units	(1,584)	(2,653)
Other financing activities	(365)	302
Net cash provided by (used in) financing activities	217,712	(208,227)
NET INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	197,114	125,794
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	177,702	72,595
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	$ 374,816	$ 198,389

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Partners' Capital - USD ($) $ in Thousands	Total	AIMCO Properties, LP [Member]	AIMCO Properties, LP [Member]Preferred Units [Member]	AIMCO Properties, LP [Member]General Partner and Special Limited Partner [Member]	AIMCO Properties, LP [Member]Limited Partners [Member]	AIMCO Properties, LP [Member]Partners Capital Attributable To The Partnership [Member]	AIMCO Properties, LP [Member]Noncontrolling Interests In Consolidated Real Estate Partnerships
Balances at Dec. 31, 2018		$ 1,763,641	$ 125,000	$ 1,574,419	$ 67,189	$ 1,766,608	$ (2,967)
Increase (Decrease) in Partners' Capital [Roll Forward]
Repurchases of common partnership units		(20,682)		(20,682)		(20,682)
Redemption of Aimco Operating Partnership units		(2,557)			(2,557)	(2,557)
Amortization of share-based compensation cost		3,238		2,442	796	3,238
Effect of changes in ownership of consolidated entities				(2,168)	2,168
Change in accumulated other comprehensive income	$ 61	61		57	4	61
Net income	289,361	289,361		274,133	15,137	289,270	91
Distributions paid to common unitholders		(70,720)		(67,476)	(3,244)	(70,720)
Distributions paid to preferred unitholders		(2,148)		(2,148)		(2,148)
Distributions to noncontrolling interests	(3,244)
Other, net		78		59		59	19
Balances at Mar. 31, 2019		1,960,272	$ 125,000	1,758,636	79,493	1,963,129	(2,857)
Balances at Dec. 31, 2019		1,860,795		1,780,649	83,442	1,864,091	(3,296)
Increase (Decrease) in Partners' Capital [Roll Forward]
Repurchases of common partnership units		(10,004)		(10,004)		(10,004)
Redemption of Aimco Operating Partnership units		(969)			(969)	(969)
Amortization of share-based compensation cost		2,980		1,929	1,051	2,980
Effect of changes in ownership of consolidated entities				(769)	769
Change in accumulated other comprehensive income	(60)	(60)		(56)	(4)	(60)
Net income	7,208	7,208		6,722	368	7,090	118
Distributions paid to common unitholders		(63,980)		(60,825)	(3,155)	(63,980)
Distributions to noncontrolling interests	(3,228)	(73)					(73)
Other, net		(72)		86		86	(158)
Balances at Mar. 31, 2020		1,795,548		1,717,455	$ 81,502	1,798,957	$ (3,409)
Increase (Decrease) in Partners' Capital [Roll Forward]
Cumulative effect of a change in accounting principle	$ (277)	$ (277)		$ (277)		$ (277)

Organization

Organization	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization	Note 1 — Organization Apartment Investment and Management Company, or Aimco, is a Maryland corporation incorporated on January 10, 1994. Aimco is a self-administered and self-managed real estate investment trust, or REIT. AIMCO Properties, L.P., or the Aimco Operating Partnership, is a Delaware limited partnership formed on May 16, 1994, to conduct our business, which is focused on the ownership, management, redevelopment, and some development of quality apartment communities located in several of the largest markets in the United States. Aimco, through its wholly-owned subsidiaries, AIMCO-GP, Inc. and AIMCO-LP Trust, holds a majority of the ownership interests in the Aimco Operating Partnership. Aimco conducts all of its business and owns all of its assets through the Aimco Operating Partnership. Interests in the Aimco Operating Partnership that are held by limited partners other than Aimco 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 March 31, 2020, after elimination of units held by consolidated subsidiaries, the Aimco Operating Partnership had 159,196,780 common OP Units outstanding. As of March 31, 2020, Aimco owned 148,700,407 of the common OP Units of the Aimco Operating Partnership and Aimco had an equal number of shares of its Class A Common Stock outstanding, which we refer to as Common Stock. Aimco’s ownership of the total common OP units outstanding represents a 93.4% legal interest in the Aimco Operating Partnership and a 94.8% economic interest. Except as the context otherwise requires, “we,” “our,” and “us” refer to Aimco, the Aimco Operating Partnership, and their consolidated subsidiaries, collectively. We own and operate a portfolio of apartment communities, diversified by both geography and price point, in 17 states and the District of Columbia. As of March 31, 2020, our portfolio included 124 apartment communities with 32,846 apartment homes in which we held an average ownership of approximately 99%. We consolidated 120 of these apartment communities with 32,704 apartment homes.

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Note 2 — Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted in accordance with such rules and regulations, although management believes the disclosures are adequate to prevent the information presented from being misleading. In the opinion of management, all adjustments, consisting of normal recurring items, considered necessary for a fair presentation have been included. Operating results for the three months ended March 31, 2020, are not necessarily indicative of the results that may be expected for the year ending December 31, 2020. The condensed consolidated balance sheets of Aimco and the Aimco Operating Partnership at December 31, 2019, have been derived from their respective audited financial statements at that date, but do not include all of the information and disclosures required by GAAP for complete financial statements. For further information, refer to the financial statements and notes thereto included in Aimco’s and the Aimco Operating Partnership’s combined Annual Report on Form 10-K for the year ended December 31, 2019. Except where indicated, the footnotes refer to both Aimco and the Aimco Operating Partnership. Principles of Consolidation Aimco’s accompanying condensed consolidated financial statements include the accounts of Aimco, the Aimco Operating Partnership, and their consolidated subsidiaries. The Aimco Operating Partnership’s condensed consolidated financial statements include the accounts of the Aimco Operating Partnership and its consolidated subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. We consolidate a variable interest entity, or 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 March 31, 2020, and December 31, 2019, Aimco consolidated six VIEs, in addition to the Aimco Operating Partnership. 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 Aimco Operating Partnership that are held by limited partners other than Aimco are reflected in Aimco’s accompanying condensed consolidated balance sheets as noncontrolling interests in the Aimco Operating Partnership. Interests in partnerships consolidated by the Aimco Operating Partnership that are held by third parties are reflected in our accompanying condensed consolidated balance sheets as noncontrolling interests in consolidated real estate partnerships. 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. We loaned $275 million to the partnership, which accrues interest at 10% per annum with a five-year five-year Redeemable Preferred OP Units As described in Note 5, the preferred OP Units may be redeemed at the holder’s option and are therefore presented within temporary equity in Aimco’s condensed consolidated balance sheets and within temporary capital in the Aimco Operating Partnership’s condensed consolidated balance sheets. The following table presents a reconciliation of the Aimco Operating Partnership’s preferred OP Units from December 31, 2019, to March 31, 2020 (in thousands): 2020 Balance at December 31 $ 97,064 Preferred distributions (1,869 ) Redemption of preferred units (615 ) Net income 1,869 Balance at March 31 $ 96,449 The Aimco Operating Partnership has outstanding various classes of redeemable preferred OP Units. As of March 31, 2020, the Aimco Operating Partnership had 3,618,802 redeemable preferred OP Units issued and outstanding with a total redemption value of $96.4 million. Distributions per annum range from 1.92% to 8.75% per class and from $0.48 to $8.00 per unit. Revenue from Leases The majority of lease payments we receive from our residents and tenants are fixed. We receive variable payments from our residents and commercial tenants primarily for utility reimbursements. For the three months ended March 31, 2020 and 2019, our total lease income was comprised of the following amounts for all operating leases (in thousands): 2020 2019 Fixed lease income $ 213,416 $ 215,581 Variable lease income 13,615 14,144 Total lease income $ 227,031 $ 229,725 We monitor the collectability of unpaid rent obligations and due to the impact of COVID-19 and the resulting economic impact on our commercial tenants, we recognized a write-off of straight-line rent receivables and deferred leasing costs of $2.9 million and $2.2 million, respectively. The write-off of the straight-line rent receivables is not included in the fixed lease income in the table above. Use of Estimates The preparation of our condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts included in the financial statements and accompanying notes thereto. Actual results could differ from those estimates. Reclassifications and Revisions For the 2020 presentation of our condensed consolidated statements of operations, we have added a caption for investment management expenses. We have reclassified certain items from property operating expenses, general and administrative expenses, and other expenses, net, in our 2019 presentation to conform to the current presentation. Accounting Pronouncements Adopted in the Current Year On January 1, 2020, we adopted ASC 326, Financial Instruments – Credit Losses We adopted the credit loss standard using the modified-retrospective approach. We recorded a cumulative-effect adjustment for the estimated credit loss associated with our notes receivable of $0.3 million in distributions in excess of earnings and partners’ capital in our condensed consolidated balance sheets as of January 1, 2020. As of the date of adoption, the fair value of our AFS debt securities exceeded their carrying value and no estimate of credit loss was required for these instruments.

Significant Transactions

Significant Transactions	3 Months Ended
	Mar. 31, 2020
Significant Transactions [Abstract]
Significant Transactions	Note 3 — Significant Transactions Financing Activity On April 20, 2020, we secured a $350.0 million term loan. The loan matures on April 20, 2021, includes a one-year Dispositions of Apartment Communities During the three months ended March 31, 2020, no apartment communities were sold. During the three months ended March 31, 2019 we sold apartment communities as summarized below (dollars in thousands): 2019 Number of apartment communities sold 7 Number of apartment homes sold 2,206 Gain on dispositions of real estate $ 291,473 The apartment communities sold were predominantly located outside of our primary markets or in lower-rated locations within our primary markets and had average revenues per apartment home significantly below those of our retained portfolio. From time to time we may be marketing for sale certain apartment communities that are inconsistent with our long-term investment strategy. At the end of each reporting period we evaluate whether such communities meet the criteria to be classified as held for sale. As of March 31, 2020, no apartment communities were classified as held for sale.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 4 — Commitments and Contingencies Commitments In connection with our redevelopment, development and other capital additions activities, we have entered into various construction-related contracts and we have made commitments to complete redevelopment and development of certain apartment communities, pursuant to financing or other arrangements. As of March 31, 2020, our commitments related to these capital activities totaled approximately $219.0 million, most of which we expect to incur during the next 12 months. 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, or EPA, regarding contaminated groundwater near an Indiana apartment community that has not been owned by us since 2008. 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, or 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 a scope of work and agreed order to finish clean up of the site outside the Superfund program. Although the outcome of these processes are uncertain, we do not expect their resolution to have a material adverse effect on our consolidated financial condition, results of operations or cash flows. We also have a contingent environmental 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, or 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 are appealing the final order while simultaneously complying with it. Although the outcome of this process is uncertain, we do not expect its 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, 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 asset retirement obligations cannot be reasonably estimated due to significant uncertainties in the timing and manner of settlement of those obligations. Asset retirement obligations that are reasonably estimable as of March 31, 2020, are immaterial to our consolidated financial condition, results of operations and cash flows.

Earnings and Dividends per Shar

Earnings and Dividends per Share and Unit	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Earnings and Dividends per Share and Unit	Note 5 — Earnings and Dividends per Share and Unit Aimco and the Aimco Operating Partnership calculate basic earnings per common share and basic earnings per common unit based on the weighted average number of shares of Common Stock and common partnership units outstanding. 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 options to purchase shares of Common Stock, which, if exercised, would result in Aimco’s issuance of additional shares and the Aimco Operating Partnership’s issuance to Aimco of additional common partnership units equal to the number of shares purchased under the options. These equivalents also include unvested total shareholder return, or 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 shares that vest. 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 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, and 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 three months ended March 31, 2020 and 2019 are as follows (in thousands, except per share and per unit data): Three Months Ended March 31, 2020 March 31, 2019 Earnings per share Numerator: Basic and dilutive net income attributable to Aimco common stockholders $ 6,679 $ 271,568 Denominator - shares: Basic weighted-average Common Stock outstanding 148,518 144,232 Dilutive share equivalents outstanding 268 213 Dilutive weighted-average Common Stock outstanding 148,786 144,445 Earnings per share – basic $ 0.04 $ 1.88 Earnings per share – dilutive $ 0.04 $ 1.88 Non-dilutive share equivalents outstanding 97 36 Earnings per unit Numerator: Basic and dilutive net income attributable to the Aimco Operating Partnership's common unitholders $ 7,047 $ 286,639 Denominator - units Basic weighted-average common partnership units outstanding 156,660 152,303 Dilutive partnership unit equivalents outstanding 343 329 Dilutive weighted-average common partnership units outstanding 157,003 152,632 Earnings per unit – basic $ 0.04 $ 1.88 Earnings per unit – dilutive $ 0.04 $ 1.88 Non-dilutive partnership unit equivalents outstanding 1,847 229 The Aimco Operating Partnership has various classes of preferred OP Units, which may be redeemed at the holders’ option. The Aimco Operating Partnership may redeem these units for cash, or at its option, shares of Common Stock. As of March 31, 2020, these preferred OP Units were potentially redeemable for approximately 2.7 million shares of Common Stock (based on the period end market price), or cash. The Aimco Operating Partnership has a redemption policy that requires cash settlement of redemption requests for the preferred OP Units, subject to limited exceptions. Accordingly, we have excluded these securities from earnings per share and unit computations for the periods presented above, and we expect to exclude them in future periods. During the three months ended March 31, 2020 and 2019, we paid $0.41 and $2.02, respectively, in dividends and distributions per share and per unit. The $2.02 paid during the three months ended March 31, 2019 represents the per share and per unit value of the special dividend and special distribution authorized by the Board of Directors in the first quarter of 2019. The special dividend consisted of $67.1 million in cash, 4.5 million shares of Common Stock and $0.4 million of cash paid in lieu of issuing fractional shares. The special distribution consisted of $72.7 million in cash, 4.8 million common partnership units and $0.4 million of cash paid in lieu of issuing fractional units. In connection with the special dividend and distribution, the Board of Directors authorized a reverse stock split during the three months ended March 31, 2019. The reverse split combined every 1.03119 common shares and common partnership units into one common share or common partnership unit and was intended to neutralize the dilutive impact of the shares and units issued in the special dividend and distribution. As a result, the number of shares and units outstanding after the dividend/distribution and reverse split was unchanged from the number outstanding immediately prior to the two actions.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 6 — Fair Value Measurements Recurring Fair Value Measurements We measure at fair value on a recurring basis our investments in the securitization trust that holds certain of our property debt, which we classify as AFS debt securities. These investments are presented within other assets in the condensed consolidated balance sheets. We hold several positions in the securitization trust that pay interest currently and we also hold the first loss position in the securitization trust, which accrues interest over the term of the investment. These investments were acquired at a discount to face value and we are accreting the discount to the $100.9 million face value of the investments through interest income using the effective interest method over the remaining expected term of the investments, which as of March 31, 2020, was approximately 1.2 years. Our amortized cost basis for these investments, which represents the original cost adjusted for interest accretion less interest payments received, was $91.7 million and $90.0 million as of March 31, 2020, and December 31, 2019, respectively. Our investments in AFS debt securities are classified within Level 2 of the GAAP fair value hierarchy. We estimate the fair value of these investments using an income and market approach with primarily observable inputs, including yields and other information regarding similar types of investments, and adjusted for certain unobservable inputs specific to these investments. The fair value of the positions that pay interest currently typically moves in an inverse relationship with movements in interest rates. The fair value of the first loss position is primarily correlated to collateral quality and demand for similar subordinate commercial mortgage-backed securities. The following table summarizes fair value for our AFS debt securities (in thousands): As of March 31, 2020 As of December 31, 2019 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 AFS debt securities $ 95,906 $ — $ 95,906 $ — $ 94,251 $ — $ 94,251 $ — Non-Recurring Fair Value Measurements We believe that the carrying value of the consolidated amounts of cash and cash equivalents, restricted cash, accounts receivable, and accounts payable approximated their fair value as of March 31, 2020, and December 31, 2019, due to their relatively short-term nature and high probability of realization. The carrying amounts of notes receivable and the revolving credit facility approximated their estimated fair value as of March 31, 2020, and December 31, 2019. We estimate the fair value of our non-recourse property debt using an income and market approach, including comparison of the contractual terms to observable and unobservable inputs such as market interest rate risk spreads, contractual interest rates, remaining periods to maturity, collateral quality and loan to value ratios on similarly encumbered apartment communities within our portfolio. We classify the fair value of our non-recourse property debt within Level 2 of the GAAP valuation hierarchy based on the significance of certain of the unobservable inputs used to estimate its fair value. The following table summarizes carrying value and fair value for our non-recourse property debt (in thousands): As of March 31, 2020 As of December 31, 2019 Carrying Value Fair Value Carrying Value Fair Value Non-recourse property debt $ 4,228,440 $ 4,166,396 $ 4,251,339 $ 4,298,630

Business Segments

Business Segments	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Business Segments	Note 7 — Business Segments We have four segments: Same Store, Redevelopment and Development, Acquisition, and Other Real Estate. Our Same Store segment includes communities that have reached a stabilized level of operations as of the beginning of a two-year comparable period and maintained it throughout the current and comparable prior year and are not expected to be sold within 12 months. Our Redevelopment and Development segment includes apartment communities that are currently under construction, and those that have been completed in recent years that have not achieved and maintained stabilized operations for both the current and comparable prior year. Our Acquisition segment includes communities that we have acquired since the beginning of a two-year comparable period. Our Other Real Estate segment primarily includes communities that are subject to limitations on rent increases, communities that we expect to sell within 12 months but do not yet meet the criteria to be classified as held for sale, communities that we expect to redevelop, and certain commercial spaces. Our chief operating decision maker uses proportionate property net operating income to assess the operating performance of our communities. Proportionate property net operating income reflects our share of rental and other property revenues, excluding utility reimbursements, less direct property operating expenses, net of utility reimbursements, for consolidated communities. In our condensed consolidated statements of operations, utility reimbursements are included in rental and other property revenues, in accordance with GAAP . As of March 31, 2020, our Same Store segment included 95 consolidated apartment communities with 28,095 apartment homes; our Redevelopment and Development segment included six consolidated communities with 2,210 homes; our Acquisition segment included one consolidated community with 110 homes, and one consolidated community with 136 homes under construction; and our Other Real Estate segment included 18 communities with 2,289 homes and one office building. The following tables present the rental and other property revenues, property operating expenses, proportionate property net operating income, and income before income tax benefit (expense) of our segments on a proportionate basis, excluding amounts related to sold communities and our proportionate share of four apartment communities with 142 apartment homes that we neither manage nor consolidate, for the three months ended March 31, 2020 and 2019 (in thousands): Same Store Redevelopment and Development Acquisition Other Real Estate Proportionate and Other Adjustments (1) Corporate and Amounts Not Allocated to Segments (2) Consolidated Three months ended March 31, 2020: Rental and other property revenues $ 187,956 $ 11,913 $ 884 $ 17,875 $ 8,812 $ (2,888 ) $ 224,552 Property operating expenses 48,782 4,687 401 6,174 8,175 7,261 75,480 Other operating expenses not allocated to segments (3) — — — — — 113,410 113,410 Total operating expenses 48,782 4,687 401 6,174 8,175 120,671 188,890 Proportionate property net operating income (loss) 139,174 7,226 483 11,701 637 (123,559 ) 35,662 Other items included in income before income tax benefit (4) — — — — — (29,918 ) (29,918 ) Income before income tax benefit $ 139,174 $ 7,226 $ 483 $ 11,701 $ 637 $ (153,477 ) $ 5,744 Same Store Redevelopment and Development Acquisition Other Real Estate Proportionate and Other Adjustments (1) Corporate and Amounts Not Allocated to Segments (2) Consolidated Three months ended March 31, 2019: Rental and other property revenues $ 181,523 $ 14,012 $ — $ 14,113 $ 8,292 $ 12,295 $ 230,235 Property operating expenses 48,990 5,255 127 4,991 7,733 11,863 78,959 Other operating expenses not allocated to segments (3) — — — — — 109,862 109,862 Total operating expenses 48,990 5,255 127 4,991 7,733 121,725 188,821 Proportionate property net operating income (loss) 132,533 8,757 (127 ) 9,122 559 (109,430 ) 41,414 Other items included in income before income tax expense (4) — — — — — 252,862 252,862 Income before income tax expense $ 132,533 $ 8,757 $ (127 ) $ 9,122 $ 559 $ 143,432 $ 294,276 (1) Represents adjustments for the noncontrolling interests in consolidated real estate partnerships’ share of the results of consolidated communities in our segments, which are included in the related consolidated amounts, but excluded from proportionate property net operating income for our segment evaluation. 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 condensed consolidated statements of operations prepared in accordance with GAAP. (2) Includes the operating results of apartment communities sold during the periods shown or held for sale at the end of the period, if any. Also includes property management expenses and casualty gains and losses, which are included in consolidated property operating expenses and are not part of our segment performance measure. Write-off of straight-line rent receivables, which was recognized due to the impact of COVID-19 and the resulting economic impact on our commercial tenants, is included in consolidated rental and other property revenues. The write-off of straight-line rent is not included in our measurement of segment performance. (3) Includes depreciation and amortization, general and administrative expenses, and other operating expenses including provision for real estate impairment loss, which are not included in our measure of segment performance. (4) Includes gain (loss) on dispositions of real estate, mezzanine investment income, interest income, and interest expense. The assets of our segments and the consolidated assets not allocated to our segments were as follows (in thousands): March 31, 2020 December 31, 2019 Same Store $ 4,643,371 $ 4,679,211 Redevelopment and Development 731,811 694,188 Acquisition 102,217 89,405 Other Real Estate 733,138 736,934 Corporate and other assets (1) 837,708 629,001 Total consolidated assets $ 7,048,245 $ 6,828,739 (1) Includes the assets not allocated to our segments, primarily corporate assets and assets of sold apartment communities. For the three months ended March 31, 2020 and 2019, capital additions related to our segments were as follows (in thousands): 2020 2019 Same Store $ 27,526 $ 35,379 Redevelopment and Development 44,596 36,458 Acquisition 15,343 76 Other Real Estate 6,419 3,477 Total capital additions $ 93,884 $ 75,390

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Note 8 – Subsequent Events In December 2019, COVID-19 was first identified during an investigation into an outbreak in Wuhan, China. The World Health Organization declared COVID-19 to be a pandemic on March 11, 2020. The outbreak of the COVID-19 pandemic has severely impacted global economic activity and caused significant volatility and negative pressure in financial markets. Many states and local jurisdictions have reacted by instituting a wide variety of measures including states of emergency, mandatory quarantines, required business and school closures, implementing “shelter in place” orders, and restricting travel. In addition, many cities and states have enacted, or are considering enacting, protections for residents and commercial tenants, including government mandated rent delays, other abatement measures or concessions, and prohibitions on lease terminations or evictions for tenants. Many experts predict that the outbreak will trigger a period of material global economic slowdown or a global recession. We will continue to monitor impairments of our real estate assets, impairment of our mezzanine loan investment, and estimates of bad debt on rental income. The unknown duration of the pandemic, any limitations that prevent us from enforcing our legal right, and the resulting economy are expected to likely result in increased bad debt and lower occupancy, negatively impacting our results. We will continue to monitor the collectability of all unpaid commercial rent obligations and may be required to make further write-offs in the future. Additionally, we will continue to monitor economic and market conditions and provide no assurance that a prolonged recession will not result in a non-cash impairment loss in the future. On April 10, 2020, the FASB issued a Staff Q&A to respond to some frequently asked questions about accounting for lease concessions, including deferrals or reductions of future lease payments. Consequently, in accordance with the Staff Q&A issued by the FASB, we may elect to not follow lease modification accounting for concessions related to the effects of the COVID-19 pandemic. We are currently working with tenants impacted by the COVID-19 pandemic and will continue to evaluate the accounting impact of future lease concessions.

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted in accordance with such rules and regulations, although management believes the disclosures are adequate to prevent the information presented from being misleading. In the opinion of management, all adjustments, consisting of normal recurring items, considered necessary for a fair presentation have been included. Operating results for the three months ended March 31, 2020, are not necessarily indicative of the results that may be expected for the year ending December 31, 2020. The condensed consolidated balance sheets of Aimco and the Aimco Operating Partnership at December 31, 2019, have been derived from their respective audited financial statements at that date, but do not include all of the information and disclosures required by GAAP for complete financial statements. For further information, refer to the financial statements and notes thereto included in Aimco’s and the Aimco Operating Partnership’s combined Annual Report on Form 10-K for the year ended December 31, 2019. Except where indicated, the footnotes refer to both Aimco and the Aimco Operating Partnership.
Principles of Consolidation	Principles of Consolidation Aimco’s accompanying condensed consolidated financial statements include the accounts of Aimco, the Aimco Operating Partnership, and their consolidated subsidiaries. The Aimco Operating Partnership’s condensed consolidated financial statements include the accounts of the Aimco Operating Partnership and its consolidated subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. We consolidate a variable interest entity, or 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 March 31, 2020, and December 31, 2019, Aimco consolidated six VIEs, in addition to the Aimco Operating Partnership. 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 Aimco Operating Partnership that are held by limited partners other than Aimco are reflected in Aimco’s accompanying condensed consolidated balance sheets as noncontrolling interests in the Aimco Operating Partnership. Interests in partnerships consolidated by the Aimco Operating Partnership that are held by third parties are reflected in our accompanying condensed consolidated balance sheets as noncontrolling interests in consolidated real estate partnerships. 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. We loaned $275 million to the partnership, which accrues interest at 10% per annum with a five-year five-year
Redeemable Preferred OP Units	Redeemable Preferred OP Units As described in Note 5, the preferred OP Units may be redeemed at the holder’s option and are therefore presented within temporary equity in Aimco’s condensed consolidated balance sheets and within temporary capital in the Aimco Operating Partnership’s condensed consolidated balance sheets. The following table presents a reconciliation of the Aimco Operating Partnership’s preferred OP Units from December 31, 2019, to March 31, 2020 (in thousands): 2020 Balance at December 31 $ 97,064 Preferred distributions (1,869 ) Redemption of preferred units (615 ) Net income 1,869 Balance at March 31 $ 96,449 The Aimco Operating Partnership has outstanding various classes of redeemable preferred OP Units. As of March 31, 2020, the Aimco Operating Partnership had 3,618,802 redeemable preferred OP Units issued and outstanding with a total redemption value of $96.4 million. Distributions per annum range from 1.92% to 8.75% per class and from $0.48 to $8.00 per unit.
Revenue from Leases	Revenue from Leases The majority of lease payments we receive from our residents and tenants are fixed. We receive variable payments from our residents and commercial tenants primarily for utility reimbursements. For the three months ended March 31, 2020 and 2019, our total lease income was comprised of the following amounts for all operating leases (in thousands): 2020 2019 Fixed lease income $ 213,416 $ 215,581 Variable lease income 13,615 14,144 Total lease income $ 227,031 $ 229,725 We monitor the collectability of unpaid rent obligations and due to the impact of COVID-19 and the resulting economic impact on our commercial tenants, we recognized a write-off of straight-line rent receivables and deferred leasing costs of $2.9 million and $2.2 million, respectively. The write-off of the straight-line rent receivables is not included in the fixed lease income in the table above.
Use of Estimates	Use of Estimates The preparation of our condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts included in the financial statements and accompanying notes thereto. Actual results could differ from those estimates.
Reclassifications and Revisions	Reclassifications and Revisions For the 2020 presentation of our condensed consolidated statements of operations, we have added a caption for investment management expenses. We have reclassified certain items from property operating expenses, general and administrative expenses, and other expenses, net, in our 2019 presentation to conform to the current presentation.
Accounting Pronouncements Adopted in the Current Year	Accounting Pronouncements Adopted in the Current Year On January 1, 2020, we adopted ASC 326, Financial Instruments – Credit Losses We adopted the credit loss standard using the modified-retrospective approach. We recorded a cumulative-effect adjustment for the estimated credit loss associated with our notes receivable of $0.3 million in distributions in excess of earnings and partners’ capital in our condensed consolidated balance sheets as of January 1, 2020. As of the date of adoption, the fair value of our AFS debt securities exceeded their carrying value and no estimate of credit loss was required for these instruments.
Fair Value of Financial Instruments	Recurring Fair Value Measurements

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Reconciliation of Preferred OP Units	As described in Note 5, the preferred OP Units may be redeemed at the holder’s option and are therefore presented within temporary equity in Aimco’s condensed consolidated balance sheets and within temporary capital in the Aimco Operating Partnership’s condensed consolidated balance sheets. The following table presents a reconciliation of the Aimco Operating Partnership’s preferred OP Units from December 31, 2019, to March 31, 2020 (in thousands): 2020 Balance at December 31 $ 97,064 Preferred distributions (1,869 ) Redemption of preferred units (615 ) Net income 1,869 Balance at March 31 $ 96,449
Lease Income for Operating Leases	The majority of lease payments we receive from our residents and tenants are fixed. We receive variable payments from our residents and commercial tenants primarily for utility reimbursements. For the three months ended March 31, 2020 and 2019, our total lease income was comprised of the following amounts for all operating leases (in thousands): 2020 2019 Fixed lease income $ 213,416 $ 215,581 Variable lease income 13,615 14,144 Total lease income $ 227,031 $ 229,725

Significant Transactions (Table

Significant Transactions (Tables)	3 Months Ended
	Mar. 31, 2020
Significant Transactions [Abstract]
Summary of Apartment Community Dispositions	During the three months ended March 31, 2020, no apartment communities were sold. During the three months ended March 31, 2019 we sold apartment communities as summarized below (dollars in thousands): 2019 Number of apartment communities sold 7 Number of apartment homes sold 2,206 Gain on dispositions of real estate $ 291,473

Earnings and Dividends per Sh_2

Earnings and Dividends per Share and Unit (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Effect of Dilutive Securities and Securities not Dilutive	Reconciliations of the numerator and denominator in the calculations of basic and diluted earnings per share and per unit for the three months ended March 31, 2020 and 2019 are as follows (in thousands, except per share and per unit data): Three Months Ended March 31, 2020 March 31, 2019 Earnings per share Numerator: Basic and dilutive net income attributable to Aimco common stockholders $ 6,679 $ 271,568 Denominator - shares: Basic weighted-average Common Stock outstanding 148,518 144,232 Dilutive share equivalents outstanding 268 213 Dilutive weighted-average Common Stock outstanding 148,786 144,445 Earnings per share – basic $ 0.04 $ 1.88 Earnings per share – dilutive $ 0.04 $ 1.88 Non-dilutive share equivalents outstanding 97 36 Earnings per unit Numerator: Basic and dilutive net income attributable to the Aimco Operating Partnership's common unitholders $ 7,047 $ 286,639 Denominator - units Basic weighted-average common partnership units outstanding 156,660 152,303 Dilutive partnership unit equivalents outstanding 343 329 Dilutive weighted-average common partnership units outstanding 157,003 152,632 Earnings per unit – basic $ 0.04 $ 1.88 Earnings per unit – dilutive $ 0.04 $ 1.88 Non-dilutive partnership unit equivalents outstanding 1,847 229

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Summary of Fair Value for AFS Debt Securities	The following table summarizes fair value for our AFS debt securities (in thousands): As of March 31, 2020 As of December 31, 2019 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 AFS debt securities $ 95,906 $ — $ 95,906 $ — $ 94,251 $ — $ 94,251 $ —
Summary of Carrying Value and Fair Value of Non-recourse Property Debt	The following table summarizes carrying value and fair value for our non-recourse property debt (in thousands): As of March 31, 2020 As of December 31, 2019 Carrying Value Fair Value Carrying Value Fair Value Non-recourse property debt $ 4,228,440 $ 4,166,396 $ 4,251,339 $ 4,298,630

Business Segments (Tables)

Business Segments (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Summary of Information for Reportable Segments	The following tables present the rental and other property revenues, property operating expenses, proportionate property net operating income, and income before income tax benefit (expense) of our segments on a proportionate basis, excluding amounts related to sold communities and our proportionate share of four apartment communities with 142 apartment homes that we neither manage nor consolidate, for the three months ended March 31, 2020 and 2019 (in thousands): Same Store Redevelopment and Development Acquisition Other Real Estate Proportionate and Other Adjustments (1) Corporate and Amounts Not Allocated to Segments (2) Consolidated Three months ended March 31, 2020: Rental and other property revenues $ 187,956 $ 11,913 $ 884 $ 17,875 $ 8,812 $ (2,888 ) $ 224,552 Property operating expenses 48,782 4,687 401 6,174 8,175 7,261 75,480 Other operating expenses not allocated to segments (3) — — — — — 113,410 113,410 Total operating expenses 48,782 4,687 401 6,174 8,175 120,671 188,890 Proportionate property net operating income (loss) 139,174 7,226 483 11,701 637 (123,559 ) 35,662 Other items included in income before income tax benefit (4) — — — — — (29,918 ) (29,918 ) Income before income tax benefit $ 139,174 $ 7,226 $ 483 $ 11,701 $ 637 $ (153,477 ) $ 5,744 Same Store Redevelopment and Development Acquisition Other Real Estate Proportionate and Other Adjustments (1) Corporate and Amounts Not Allocated to Segments (2) Consolidated Three months ended March 31, 2019: Rental and other property revenues $ 181,523 $ 14,012 $ — $ 14,113 $ 8,292 $ 12,295 $ 230,235 Property operating expenses 48,990 5,255 127 4,991 7,733 11,863 78,959 Other operating expenses not allocated to segments (3) — — — — — 109,862 109,862 Total operating expenses 48,990 5,255 127 4,991 7,733 121,725 188,821 Proportionate property net operating income (loss) 132,533 8,757 (127 ) 9,122 559 (109,430 ) 41,414 Other items included in income before income tax expense (4) — — — — — 252,862 252,862 Income before income tax expense $ 132,533 $ 8,757 $ (127 ) $ 9,122 $ 559 $ 143,432 $ 294,276 (1) Represents adjustments for the noncontrolling interests in consolidated real estate partnerships’ share of the results of consolidated communities in our segments, which are included in the related consolidated amounts, but excluded from proportionate property net operating income for our segment evaluation. 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 condensed consolidated statements of operations prepared in accordance with GAAP. (2) Includes the operating results of apartment communities sold during the periods shown or held for sale at the end of the period, if any. Also includes property management expenses and casualty gains and losses, which are included in consolidated property operating expenses and are not part of our segment performance measure. Write-off of straight-line rent receivables, which was recognized due to the impact of COVID-19 and the resulting economic impact on our commercial tenants, is included in consolidated rental and other property revenues. The write-off of straight-line rent is not included in our measurement of segment performance. (3) Includes depreciation and amortization, general and administrative expenses, and other operating expenses including provision for real estate impairment loss, which are not included in our measure of segment performance. (4) Includes gain (loss) on dispositions of real estate, mezzanine investment income, interest income, and interest expense.
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): March 31, 2020 December 31, 2019 Same Store $ 4,643,371 $ 4,679,211 Redevelopment and Development 731,811 694,188 Acquisition 102,217 89,405 Other Real Estate 733,138 736,934 Corporate and other assets (1) 837,708 629,001 Total consolidated assets $ 7,048,245 $ 6,828,739 (1) Includes the assets not allocated to our segments, primarily corporate assets and assets of sold apartment communities.
Capital Additions Related to Segments	For the three months ended March 31, 2020 and 2019, capital additions related to our segments were as follows (in thousands): 2020 2019 Same Store $ 27,526 $ 35,379 Redevelopment and Development 44,596 36,458 Acquisition 15,343 76 Other Real Estate 6,419 3,477 Total capital additions $ 93,884 $ 75,390

Organization (Details Textual)

Organization (Details Textual)	3 Months Ended
	Mar. 31, 2020Propertyapartment_homeshares
Partially Owned Properties [Member]
Organization [Line Items]
Number of apartment communities | Property	124
Number of apartment homes in apartment communities | apartment_home	32,846
Percentage of average ownership of portfolio	99.00%
Wholly And Partially Owned Consolidated Properties [Member]
Organization [Line Items]
Number of apartment communities | Property	120
Number of apartment homes in apartment communities | apartment_home	32,704
AIMCO PROPERTIES, L.P [Member]
Organization [Line Items]
Common operating partnership units and equivalents outstanding | shares	159,196,780
Common operating partnership units and equivalents outstanding | shares	148,700,407
Percentage of the Aimco Operating Partnership's common partnership units and equivalents owned by Aimco	93.40%
Percentage of economic interest	94.80%

Basis of Presentation and Sum_4

Basis of Presentation and Summary of Significant Accounting Policies (Details Textual)	3 Months Ended
	Mar. 31, 2020USD ($)Entity$ / sharesshares	Mar. 31, 2019$ / shares	Dec. 31, 2019USD ($)Entity
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of consolidated variable interest entities | Entity	6		6
Mezzanine investment	$ 286,472,000		$ 280,258,000
Distributions per annum (in dollars per share) | $ / shares	$ 0.41	$ 2.02
Write off of straight line rent receivables	$ 2,900,000
Deferred leasing costs	2,200,000
Estimate of credit loss	0
ASC 326 [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Cumulative effect adjustment for estimated credit loss	$ (300,000)
AIMCO PROPERTIES, L.P [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Units issued (in shares) | shares	3,618,802
Units outstanding (in shares) | shares	3,618,802
Redemption values	$ 96,400,000
AIMCO PROPERTIES, L.P [Member] | Minimum [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Distributions per annum	1.92%
Distributions per annum (in dollars per share) | $ / shares	$ 0.48
AIMCO PROPERTIES, L.P [Member] | Maximum [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Distributions per annum	8.75%
Distributions per annum (in dollars per share) | $ / shares	$ 8
Parkmerced Investment [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Investment owned amount	$ 275,000,000
Equity method investment, interest rate percentage	10.00%
Equity method investment, term	5 years
Equity method investment, right to extend term	5 years
Mezzanine investment	$ 286,500

Basis of Presentation and Sum_5

Basis of Presentation and Summary of Significant Accounting Policies - Reconciliation of Preferred OP Units (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance at December 31	$ 97,064
Balance at March 31	96,449
AIMCO PROPERTIES, L.P [Member]
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance at December 31	97,064
Preferred distributions	(1,869)
Redemption of preferred units	(615)
Net income	1,869
Balance at March 31	$ 96,449

Basis of Presentation and Sum_6

Basis of Presentation and Summary of Significant Accounting Policies - Lease Income for Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Fixed lease income	$ 213,416	$ 215,581
Variable lease income	13,615	14,144
Total lease income	$ 227,031	$ 229,725

Significant Transactions (Detai

Significant Transactions (Details Textual) $ in Millions	Apr. 20, 2020USD ($)	Mar. 31, 2020PropertyCommunity	Mar. 31, 2019Property
Wholly And Partially Owned Consolidated Properties [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities		120
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Wholly And Partially Owned Consolidated Properties [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities sold		0	7
Held-for-sale, Not Discontinued Operations
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities | Community		0
Subsequent Event [Member] | Term Loan [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Secured term loan | $	$ 350
Term loan maturity date	Apr. 20, 2021
Term loan option to extend	1 year
Variable interest rate description	currently bears interest at a 30-day LIBOR plus 1.85%, with a 50-basis point LIBOR floor.
Subsequent Event [Member] | Term Loan [Member] | 30-Day LIBOR [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Spread on variable interest rate	1.85%
Subsequent Event [Member] | Term Loan [Member] | LIBOR Floor [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Spread on variable interest rate	0.50%

Significant Transactions - Summ

Significant Transactions - Summary of Apartment Community Dispositions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)Property	Mar. 31, 2019USD ($)Propertyapartment_home
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain on dispositions of real estate	$ (34)	$ 291,473
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Wholly And Partially Owned Consolidated Properties [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Number of apartment communities sold | Property	0	7
Number of apartment homes sold | apartment_home		2,206
Gain on dispositions of real estate		$ 291,473

Commitments and Contingencies (

Commitments and Contingencies (Details Textual) $ in Millions	1 Months Ended	3 Months Ended
	May 31, 2017Party	Mar. 31, 2020USD ($)
Long-term Purchase Commitment [Line Items]
Number of potentially-responsible parties | Party	4
Commitments related to development, redevelopment and capital improvement activities [Member]
Long-term Purchase Commitment [Line Items]
Commitments related to capital spending activities | $		$ 219
Time Period of Long-term Purchase Commitment		12 months
Commitments related to operations [Member] | Maximum [Member]
Long-term Purchase Commitment [Line Items]
Time Period of Long-term Purchase Commitment		1 year

Earnings and Dividends per Sh_3

Earnings and Dividends per Share and Unit - Effect of Dilutive Securities and Securities not Dilutive (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Basic and dilutive net income attributable to Aimco common stockholders	$ 6,679	$ 271,568
Basic weighted-average Common Stock outstanding	148,518	144,232
Dilutive share equivalents outstanding	268	213
Dilutive weighted-average Common Stock outstanding	148,786	144,445
Earnings per share – basic	$ 0.04	$ 1.88
Earnings per share – dilutive	$ 0.04	$ 1.88
Non-dilutive share equivalents outstanding	97	36
AIMCO Properties, LP [Member]
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Basic and dilutive net income attributable to Aimco common stockholders	$ 7,047	$ 286,639
Basic weighted-average Common Stock outstanding	156,660	152,303
Dilutive share equivalents outstanding	343	329
Dilutive weighted-average Common Stock outstanding	157,003	152,632
Earnings per share – basic	$ 0.04	$ 1.88
Earnings per share – dilutive	$ 0.04	$ 1.88
Non-dilutive share equivalents outstanding	1,847	229

Earnings and Dividends per Sh_4

Earnings and Dividends per Share and Unit (Details Textual) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended
	Mar. 31, 2020USD ($)$ / sharesshares	Mar. 31, 2019USD ($)$ / shares
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Number of shares potentially redeemable for (in shares) | shares	2.7
Dividends paid (in dollars per share) | $ / shares	$ 0.41	$ 2.02
Distributions paid (in dollars per share) | $ / shares	$ 0.41	$ 2.02
Special dividend	$ 60,825	$ 67,476
Equity reverse stock split	1.03119
AIMCO Properties, LP [Member]
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Special distribution	$ 63,980	70,720
AIMCO Properties, LP [Member] | General Partner and Special Limited Partner [Member]
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Special distribution	$ 60,825	$ 67,476
Special Dividend and Special Distribution [Member]
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Dividends paid (in dollars per share) | $ / shares	$ 2.02
Special Dividend Paid [Member]
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Special dividend	$ 67,100
Common shares issued in special dividend (in shares) | shares	4.5
Special dividend, cash paid in lieu of fractional shares	$ 400
Special Cash Distribution [Member] | AIMCO Properties, LP [Member] | General Partner and Special Limited Partner [Member]
Schedule of Earnings Per Share and Dividends Per Share [Line Items]
Special distribution	$ 72,700
Units issued in special dividend (in shares) | shares	4.8
Special distribution, cash paid in lieu of fractional shares	$ 400

Fair Value Measurements (Detail

Fair Value Measurements (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Amortized cost of the investment in available-for-sale debt securities	$ 91.7	$ 90
Available-for-sale Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Face amount of investment in available-for-sale debt securities	$ 100.9
Expected remaining term of available for sale securities	1 year 2 months 12 days

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Fair Value for AFS Debt Securities (Details) - Fair value recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
AFS debt securities	$ 95,906	$ 94,251
Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
AFS debt securities	0	0
Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
AFS debt securities	95,906	94,251
Level 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
AFS debt securities	$ 0	$ 0

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Carrying Value and Fair Value of Non-recourse Property Debt (Details) - Non-recourse property debt [Member] - Fair value Non-recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Carrying Value [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Non-recourse property debt	$ 4,228,440	$ 4,251,339
Fair Value [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Non-recourse property debt	$ 4,166,396	$ 4,298,630

Business Segments (Details Text

Business Segments (Details Textual)	3 Months Ended
	Mar. 31, 2020Propertyapartment_homeSegmentoffice_building
Business Segments (Textual) [Abstract]
Number of reportable segments | Segment	4
Wholly And Partially Owned Consolidated Properties [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	120
Number of apartment homes in apartment communities | apartment_home	32,704
Wholly And Partially Owned Consolidated Properties [Member] | Same Store [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	95
Number of apartment homes in apartment communities | apartment_home	28,095
Wholly And Partially Owned Consolidated Properties [Member] | Redevelopment and Development [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	6
Number of apartment homes in apartment communities | apartment_home	2,210
Wholly And Partially Owned Consolidated Properties [Member] | Acquisition [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	1
Number of apartment homes in apartment communities | apartment_home	110
Wholly And Partially Owned Consolidated Properties [Member] | Other Real Estate [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	18
Number of apartment homes in apartment communities | apartment_home	2,289
Wholly And Partially Owned Consolidated Properties [Member] | Other Real Estate [Member] | Office Building [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | office_building	1
Wholly And Partially Owned Consolidated Properties [Member] | Under Construction [Member] | Acquisition [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	1
Number of apartment homes in apartment communities | apartment_home	136
Unconsolidated Properties [Member]
Business Segments (Textual) [Abstract]
Number of owned and managed apartment communities in segments | Property	4
Number of apartment homes in apartment communities | apartment_home	142

Business Segments - Summary of

Business Segments - Summary of Information for Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Summary information for the reportable segments
Rental and other property revenues	$ 224,552	$ 230,235
Property operating expenses	75,480	78,959
Other operating expenses not allocated to segments	113,410	109,862
Total operating expenses	188,890	188,821
Proportionate property net operating income (loss)	35,662	41,414
Other items included in income before income tax benefit (expense)	(29,918)	252,862
Income before income tax benefit (expense)	5,744	294,276
Segment Reconciling Items [Member]
Summary information for the reportable segments
Rental and other property revenues	8,812	8,292
Property operating expenses	8,175	7,733
Total operating expenses	8,175	7,733
Proportionate property net operating income (loss)	637	559
Income before income tax benefit (expense)	637	559
Corporate Non-Segment [Member]
Summary information for the reportable segments
Rental and other property revenues	(2,888)	12,295
Property operating expenses	7,261	11,863
Other operating expenses not allocated to segments	113,410	109,862
Total operating expenses	120,671	121,725
Proportionate property net operating income (loss)	(123,559)	(109,430)
Other items included in income before income tax benefit (expense)	(29,918)	252,862
Income before income tax benefit (expense)	(153,477)	143,432
Same Store [Member] | Operating Segments [Member]
Summary information for the reportable segments
Rental and other property revenues	187,956	181,523
Property operating expenses	48,782	48,990
Total operating expenses	48,782	48,990
Proportionate property net operating income (loss)	139,174	132,533
Income before income tax benefit (expense)	139,174	132,533
Redevelopment and Development [Member] | Operating Segments [Member]
Summary information for the reportable segments
Rental and other property revenues	11,913	14,012
Property operating expenses	4,687	5,255
Total operating expenses	4,687	5,255
Proportionate property net operating income (loss)	7,226	8,757
Income before income tax benefit (expense)	7,226	8,757
Acquisition [Member] | Operating Segments [Member]
Summary information for the reportable segments
Rental and other property revenues	884	0
Property operating expenses	401	127
Total operating expenses	401	127
Proportionate property net operating income (loss)	483	(127)
Income before income tax benefit (expense)	483	(127)
Other Real Estate [Member] | Operating Segments [Member]
Summary information for the reportable segments
Rental and other property revenues	17,875	14,113
Property operating expenses	6,174	4,991
Total operating expenses	6,174	4,991
Proportionate property net operating income (loss)	11,701	9,122
Income before income tax benefit (expense)	$ 11,701	$ 9,122

Business Segments - Reconciliat

Business Segments - Reconciliation of Assets from Segment to Consolidated (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total assets	$ 7,048,245	$ 6,828,739
Corporate Non-Segment [Member]
Segment Reporting Information [Line Items]
Total assets	837,708	629,001
Same Store [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	4,643,371	4,679,211
Redevelopment and Development [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	731,811	694,188
Acquisition [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	102,217	89,405
Other Real Estate [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	$ 733,138	$ 736,934

Business Segments - Capital Add

Business Segments - Capital Additions Related to Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Capital additions	$ 93,884	$ 75,390
Same Store [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Capital additions	27,526	35,379
Redevelopment and Development [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Capital additions	44,596	36,458
Acquisition [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Capital additions	15,343	76
Other Real Estate [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Capital additions	$ 6,419	$ 3,477