Empire State Realty Trust (ESRT) 10-Q 7 May 21 2021 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2021	Apr. 27, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-36105
Entity Registrant Name	EMPIRE STATE REALTY TRUST, INC.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	37-1645259
Entity Address, Address Line One	111 West 33rd Street
Entity Address, Address Line Two	12th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10120
City Area Code	212
Local Phone Number	850-2600
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
Entity Shell Company	false
Entity Central Index Key	0001541401
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Class A Common Stock
Document Information [Line Items]
Title of 12(b) Security	Class A Common Stock, par value $0.01 per share
Trading Symbol	ESRT
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		171,931,429
Class B Common Stock
Document Information [Line Items]
Title of 12(b) Security	Class B Common Stock, par value $0.01 per share
Entity Common Stock, Shares Outstanding		1,003,441
No Trading Symbol Flag	true

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commercial real estate properties, at cost:
Land	$ 201,196	$ 201,196
Development costs	8,064	7,966
Building and improvements	2,943,148	2,924,804
Commercial real estate properties, at cost	3,152,408	3,133,966
Less: accumulated depreciation	(973,940)	(941,612)
Commercial real estate properties, net	2,178,468	2,192,354
Cash and cash equivalents	567,102	526,714
Restricted cash	40,295	41,225
Tenant and other receivables	16,749	21,541
Deferred rent receivables	228,117	222,508
Prepaid expenses and other assets	50,427	77,182
Deferred costs, net	207,058	203,853
Acquired below-market ground leases, net	342,777	344,735
Right of use assets	29,051	29,104
Goodwill	491,479	491,479
Total assets	4,151,523	4,150,695
Liabilities:
Mortgage notes payable, net	775,276	775,929
Senior unsecured notes, net	973,214	973,159
Unsecured term loan facilities, net	387,811	387,561
Unsecured revolving credit facility	0	0
Accounts payable and accrued expenses	102,381	103,203
Acquired below-market leases, net	30,112	31,705
Ground lease liabilities	29,051	29,104
Deferred revenue and other liabilities	94,625	88,319
Tenants’ security deposits	27,858	30,408
Total liabilities	2,420,328	2,419,388
Commitments and contingencies
Empire State Realty Trust, Inc. stockholders' equity:
Preferred stock, $0.01 par value per share, 50,000,000 shares authorized, none issued or outstanding	0	0
Additional paid-in capital	1,147,588	1,147,527
Accumulated other comprehensive loss	(26,544)	(28,320)
Retained deficit	(69,272)	(65,673)
Total Empire State Realty Trust, Inc. stockholders' equity	1,053,495	1,055,249
Non-controlling interests in operating partnership	647,760	646,118
Total equity	1,731,195	1,731,307
Total liabilities and equity	4,151,523	4,150,695
Class A Common Stock
Empire State Realty Trust, Inc. stockholders' equity:
Common stock	1,713	1,705
Class B Common Stock
Empire State Realty Trust, Inc. stockholders' equity:
Common stock	10	10
Private Perpetual Preferred Units, Series 2019
Empire State Realty Trust, Inc. stockholders' equity:
Private perpetual preferred units, issued, value	21,936	21,936
Private Perpetual Preferred Units, Series 2014
Empire State Realty Trust, Inc. stockholders' equity:
Private perpetual preferred units, issued, value	$ 8,004	$ 8,004

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Equity:
Preferred stock, par value (in USD per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class A Common Stock
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	171,327,270	170,555,274
Common stock, shares outstanding (in shares)	171,327,270	170,555,274
Class B Common Stock
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	50,000,000	50,000,000
Common stock, shares issued (in shares)	1,004,601	1,010,130
Common stock, shares outstanding (in shares)	1,004,601	1,010,130
Private Perpetual Preferred Units, Series 2014
Private perpetual preferred units, per unit liquidation preference (in USD per share)	$ 16.62	$ 16.62
Private perpetual preferred units, issued (in shares)	1,560,360	1,560,360
Private perpetual preferred units, outstanding (in shares)	1,560,360	1,560,360
Private Perpetual Preferred Units, Series 2019
Private perpetual preferred units, per unit liquidation preference (in USD per share)	$ 13.52	$ 13.52
Private perpetual preferred units, issued (in shares)	4,664,038	4,664,038
Private perpetual preferred units, outstanding (in shares)	4,664,038	4,664,038

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues:
Rental revenue	$ 140,231	$ 148,113
Observatory revenue	2,603	19,544
Lease termination fees	1,289	211
Third-party management and other fees	276	346
Other revenue and fees	905	2,010
Total revenues	145,304	170,224
Operating expenses:
Property operating expenses	30,279	41,468
Ground rent expenses	2,331	2,331
General and administrative expenses	13,853	15,951
Observatory expenses	4,588	8,154
Real estate taxes	31,447	29,254
Depreciation and amortization	44,457	46,093
Total operating expenses	126,955	143,251
Total operating income	18,349	26,973
Other income (expense):
Interest income	122	637
Interest expense	(23,554)	(19,618)
Loss on early extinguishment of debt	(214)	(86)
Income (loss) before income taxes	(5,297)	7,906
Income tax benefit	2,106	382
Net income (loss)	(3,191)	8,288
Private perpetual preferred unit distributions	(1,050)	(1,050)
Net (income) loss attributable to non-controlling interests	1,620	(2,743)
Net income (loss) attributable to common stockholders	$ (2,621)	$ 4,495
Total weighted average shares:
Basic (in shares)	171,735	181,741
Diluted (in shares)	277,881	292,645
Earnings (loss) per share attributable to common stockholders:
Basic (in USD per share)	$ (0.02)	$ 0.02
Diluted (in USD per share)	(0.02)	0.02
Dividends per share (in USD per share)	$ 0	$ 0.105

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (3,191)	$ 8,288
Other comprehensive income (loss):
Unrealized gain (loss) on valuation of interest rate swap agreements	59	(17,695)
Less: amount reclassified into interest expense	2,869	796
Other comprehensive income (loss)	2,928	(16,899)
Comprehensive loss	(263)	(8,611)
Net (income) loss attributable to non-controlling interests and private perpetual preferred unitholders	570	(3,793)
Other comprehensive (income) loss attributable to non-controlling interests	(1,114)	6,405
Comprehensive loss attributable to common stockholders	$ (807)	$ (5,999)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Class A Common Stock	Class B Common Stock	Common StockClass A Common Stock	Common StockClass B Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings (Deficit)	Total Stockholders' Equity	Non-controlling Interests	Private Perpetual Preferred Units
Beginning balance (in shares) at Dec. 31, 2019				180,878,000	1,017,000
Beginning balance at Dec. 31, 2019	$ 1,947,913			$ 1,809	$ 10	$ 1,232,433	$ (21,496)	$ 15,764	$ 1,228,520	$ 690,242	$ 29,151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of private perpetual in exchange for common shares										(789)	789
Conversion of operating partnership units and Class B shares to Class A shares (in shares)				1,660,000	(2,000)
Conversion of operating partnership units and Class B shares to Class A shares	0			$ 17		7,661	(116)		7,562	(7,562)
Repurchases of common shares (in shares)				(6,571,000)
Repurchases of common shares	(62,666)			$ (65)		(44,363)		(18,238)	(62,666)
Equity compensation:
LTIP units	5,737									5,737
Restricted stock, net of forfeitures (in shares)				146,000
Restricted stock, net of forfeitures	154					154			154
Dividends and distributions	(32,651)							(18,987)	(18,987)	(12,614)	(1,050)
Net income (loss)	8,288							4,495	4,495	2,743	1,050
Other comprehensive income (loss)	(16,899)						(10,494)		(10,494)	(6,405)
Ending balance (in shares) at Mar. 31, 2020				176,113,000	1,015,000
Ending balance at Mar. 31, 2020	1,849,876			$ 1,761	$ 10	1,195,885	(32,106)	(16,966)	1,148,584	671,352	29,940
Beginning balance (in shares) at Dec. 31, 2020		170,555,274	1,010,130	170,555,000	1,010,000
Beginning balance at Dec. 31, 2020	1,731,307			$ 1,705	$ 10	1,147,527	(28,320)	(65,673)	1,055,249	646,118	29,940
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of operating partnership units and Class B shares to Class A shares (in shares)				1,071,000	(5,000)
Conversion of operating partnership units and Class B shares to Class A shares	0			$ 11		2,689	(38)		2,662	(2,662)
Repurchases of common shares (in shares)				(383,000)
Repurchases of common shares	(3,533)			$ (4)		(2,551)		(978)	(3,533)
Equity compensation:
LTIP units	4,810									4,810
Restricted stock, net of forfeitures (in shares)				84,000
Restricted stock, net of forfeitures	(76)			$ 1		(77)			(76)
Dividends and distributions	(1,050)										(1,050)
Net income (loss)	(3,191)							(2,621)	(2,621)	(1,620)	1,050
Other comprehensive income (loss)	2,928						1,814		1,814	1,114
Ending balance (in shares) at Mar. 31, 2021		171,327,270	1,004,601	171,327,000	1,005,000
Ending balance at Mar. 31, 2021	$ 1,731,195			$ 1,713	$ 10	$ 1,147,588	$ (26,544)	$ (69,272)	$ 1,053,495	$ 647,760	$ 29,940

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows From Operating Activities
Net income (loss)	$ (3,191)	$ 8,288
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	44,457	46,093
Amortization of non-cash items within interest expense	2,733	1,052
Amortization of acquired above- and below-market leases, net	(654)	(908)
Amortization of acquired below-market ground leases	1,958	1,958
Straight-lining of rental revenue	(6,347)	(8,193)
Equity based compensation	4,734	5,891
Loss on early extinguishment of debt	214	86
Increase (decrease) in cash flows due to changes in operating assets and liabilities:
Security deposits	(2,550)	(17)
Tenant and other receivables	4,792	2,874
Deferred leasing costs	(3,243)	(4,118)
Prepaid expenses and other assets	26,755	24,869
Accounts payable and accrued expenses	(3,302)	(5,261)
Deferred revenue and other liabilities	7,044	(7,840)
Net cash provided by operating activities	73,400	64,774
Cash Flows From Investing Activities
Development costs	(98)	(811)
Additions to building and improvements	(20,714)	(39,799)
Net cash used in investing activities	(20,812)	(40,610)
Cash Flows From Financing Activities
Repayment of mortgage notes payable	(1,008)	(970)
Proceeds from unsecured senior notes	0	175,000
Proceeds from unsecured term loan	0	175,000
Repayment of unsecured term loan	0	(50,000)
Proceeds from unsecured revolving credit facility	0	550,000
Deferred financing costs	(7,539)	(3,610)
Repurchases of common shares	(3,533)	(62,666)
Private perpetual preferred unit distributions	(1,050)	(1,050)
Dividends paid to common stockholders	0	(18,987)
Distributions paid to non-controlling interests in the operating partnership	0	(12,614)
Net cash (used in) provided by financing activities	(13,130)	750,103
Net increase in cash and cash equivalents and restricted cash	39,458	774,267
Cash and cash equivalents and restricted cash—beginning of period	567,939	271,597
Cash and cash equivalents and restricted cash—end of period	607,397	1,045,864
Reconciliation of Cash and Cash Equivalents and Restricted Cash:
Cash and cash equivalents at beginning of period	526,714	233,946
Restricted cash at beginning of period	41,225	37,651
Cash and cash equivalents at end of period	567,102	1,008,983
Restricted cash at end of period	40,295	36,881
Cash and cash equivalents and restricted cash	607,397	1,045,864
Supplemental disclosures of cash flow information:
Cash paid for interest	19,239	17,081
Cash paid for income taxes	13	898
Non-cash investing and financing activities:
Building and improvements included in accounts payable and accrued expenses	60,536	78,107
Write-off of fully depreciated assets	4,853	13,932
Derivative instruments at fair values included in accounts payable and accrued expenses	7,450	30,387
Conversion of operating partnership units and Class B shares to Class A shares	2,662	7,562
Issuance of Series 2019 private perpetual preferred in exchange for common shares	$ 0	$ 789

Description of Business and Org

Description of Business and Organization	3 Months Ended
	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Organization	Description of Business and Organization As used in these condensed consolidated financial statements, unless the context otherwise requires, “we,” “us,” “our,” the “company,” and "ESRT" mean Empire State Realty Trust, Inc. and its consolidated subsidiaries. We are a self-administered and self-managed real estate investment trust ("REIT") that owns, manages, operates, acquires and repositions office and retail properties in Manhattan and the greater New York metropolitan area. As of March 31, 2021, our total portfolio contained 10.1 million rentable square feet of office and retail space. We owned 14 office properties (including three long-term ground leasehold interests) encompassing approximately 9.4 million rentable square feet of office space. Nine of these properties are located in the midtown Manhattan market and aggregate approximately 7.6 million rentable square feet of office space, including the Empire State Building. Our Manhattan office properties also contain an aggregate of approximately 0.5 million rentable square feet of retail space on their ground floor and/or contiguous levels. Our remaining five office properties are located in Fairfield County, Connecticut and Westchester County, New York, encompassing in the aggregate approximately 1.8 million rentable square feet. The majority of square footage for these five properties is located in densely populated metropolitan communities with immediate access to mass transportation. Additionally, we have entitled land at the Stamford Transportation Center in Stamford, Connecticut, adjacent to one of our office properties, that will support the development of an approximately 0.4 million rentable square foot office building and garage. As of March 31, 2021, our portfolio included four standalone retail properties located in Manhattan and two standalone retail properties located in the city center of Westport, Connecticut, encompassing approximately 0.2 million rentable square feet in the aggregate.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies There have been no material changes to the summary of significant accounting policies included in the section entitled "Summary of Significant Accounting Policies" in our December 31, 2020 Annual Report on Form 10-K. Basis of Quarterly Presentation and Principles of Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”), for interim financial information, and with the rules and regulations of the Securities and Exchange Commission (the "SEC"). Accordingly, certain information and footnote disclosures required by GAAP for complete financial statements have been condensed or omitted in accordance with such rules and regulations. In the opinion of management, all adjustments and eliminations (including intercompany balances and transactions), consisting of normal recurring adjustments, considered necessary for the fair presentation of the financial statements have been included. The results of operations for the periods presented are not necessarily indicative of the results that may be expected for the corresponding full years. These financial statements should be read in conjunction with the financial statements and accompanying notes included in the financial statements for the year ended December 31, 2020 contained in our Annual Report on Form 10-K. We do not consider our business to be subject to material seasonal fluctuations, except that our observatory business is subject to tourism seasonality and currently impacted by the Coronavirus 19 ("COVID-19") pandemic. Historically, prior to the outbreak of the COVID-19 pandemic, approximately 16.0% to 18.0% of our annual observatory revenue was realized in the first quarter, 26.0% to 28.0% was realized in the second quarter, 31.0% to 33.0% was realized in the third quarter and 23.0% to 25.0% was realized in the fourth quarter. We consolidate entities in which we have a controlling financial interest. In determining whether we have a controlling financial interest in a partially owned entity and the requirement to consolidate the accounts of that entity, we consider factors such as ownership interest, board representation, management representation, authority to make decisions, and contractual and substantive participating rights of the partners/members. For variable interest entities ("VIE"), we consolidate the entity if we are deemed to have a variable interest in the entity and through that interest we are deemed the primary beneficiary. The primary beneficiary of a VIE 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. The primary beneficiary is required to consolidate the VIE. The Operating Partnership is a variable interest entity of our company, Empire State Realty Trust, Inc. As the Operating Partnership is already consolidated in the financial statements of Empire State Realty Trust, Inc., the identification of this entity as a variable interest entity has no impact on our consolidated financial statements. We will assess the accounting treatment for each investment we may have in the future. This assessment will include a review of each entity’s organizational agreement to determine which party has what rights and whether those rights are protective or participating. For all VIEs, we will review such agreements in order to determine which party has the power to direct the activities that most significantly impact the entity’s economic performance and benefit. In situations where we or our partner could approve, among other things, the annual budget, or leases that cover more than a nominal amount of space relative to the total rentable space at each property, we would not consolidate the investment as we consider these to be substantive participation rights that result in shared power of the activities that would most significantly impact the performance and benefit of such joint venture investment. A non-controlling interest in a consolidated subsidiary is defined as the portion of the equity (net assets) in a subsidiary not attributable, directly or indirectly, to a parent. Non-controlling interests are required to be presented as a separate component of equity in the condensed consolidated balance sheets and in the condensed consolidated statements of operations by requiring earnings and other comprehensive income to be attributed to controlling and non-controlling interests. Accounting Estimates The preparation of the condensed consolidated financial statements in accordance with GAAP requires management to use estimates and assumptions that in certain circumstances affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities, and the reported revenues and expenses. Significant items subject to such estimates and assumptions include allocation of the purchase price of acquired real estate properties among tangible and intangible assets, determination of the useful life of real estate properties and other long-lived assets, valuation and impairment analysis of commercial real estate properties, right of use assets and other long-lived and indefinite lived assets, estimate of tenant expense reimbursements, valuation of the allowance for doubtful accounts, and valuation of derivative instruments, ground lease liabilities, senior unsecured notes, mortgage notes payable, unsecured term loan and revolving credit facilities, and equity based compensation. These estimates are prepared using management’s best judgment, after considering past, current, and expected events and economic conditions. Actual results could differ from those estimates. Recentl y Issued or Adopted Accounting Standards During April 2020, the Financial Accounting Standards Board ("FASB") staff issued a question and answer document (the “Lease Modification Q&A”) focused on the application of lease accounting guidance to lease concessions provided as a result of the COVID-19 pandemic. Under existing lease guidance, the entity would have to determine, on a lease by lease basis, if a lease concession was the result of a new arrangement reached with the tenant, which would be accounted for under the lease modification framework, or if a lease concession was under the enforceable rights and obligations that existed in the original lease, which would be accounted for outside the lease modification framework. The Lease Modification Q&A provides entities with the option to elect to account for lease concessions as though the enforceable rights and obligations existed in the original lease. This election is only available when total cash flows resulting from the modified lease are substantially similar to the cash flows in the original lease. During March 2020, the FASB issued Accounting Standards Update ("ASU") 2020-04, Reference Rate Reform (Topic 848). ASU 2020-04 contains practical expedients for reference rate reform related activities that impact debt, leases, derivatives and other contracts. The guidance in ASU 2020-04 is optional and may be elected over time as reference rate reform activities occur. During the first quarter 2020, we elected to apply the hedge accounting expedients related to probability and the

Deferred Costs, Acquired Lease

Deferred Costs, Acquired Lease Intangibles and Goodwill	3 Months Ended
	Mar. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred Costs, Acquired Lease Intangibles and Goodwill	Deferred Costs, Acquired Lease Intangibles and Goodwill Deferred costs, net, consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Leasing costs $ 203,730 $ 203,905 Acquired in-place lease value and deferred leasing costs 180,131 181,336 Acquired above-market leases 40,254 40,398 424,115 425,639 Less: accumulated amortization (225,967) (223,918) Total deferred costs, net, excluding net deferred financing costs $ 198,148 $ 201,721 At March 31, 2021 and December 31, 2020, $8.9 million and $2.1 million, respectively, of net deferred financing costs associated with the unsecured revolving credit facility was included in deferred costs, net on the condensed consolidated balance sheet. Amortization expense related to deferred leasing costs and acquired deferred leasing costs was $5.6 million and $5.9 million for the three months ended March 31, 2021 and 2020, respectively. Amortization expense related to acquired lease intangibles was $1.7 million and $2.0 million for the three months ended March 31, 2021 and 2020, respectively. Amortizing acquired intangible assets and liabilities consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Acquired below-market ground leases $ 396,916 $ 396,916 Less: accumulated amortization (54,139) (52,181) Acquired below-market ground leases, net $ 342,777 $ 344,735 March 31, 2021 December 31, 2020 Acquired below-market leases $ (77,686) $ (78,451) Less: accumulated amortization 47,574 46,746 Acquired below-market leases, net $ (30,112) $ (31,705) Rental revenue related to the amortization of below-market leases, net of above-market leases, was $0.7 million and $0.9 million for the three months ended March 31, 2021 and 2020, respectively. As of March 31, 2021, we had goodwill of $491.5 million. Goodwill was allocated $227.5 million to the observatory reportable segment and $264.0 million to the real estate reportable segment. In compliance with the requirements of authorities, we closed the Empire State Building Observatory on March 16, 2020 due to the COVID-19 pandemic and it remained closed until the 86th floor observation deck was reopened on July 20, 2020. The 102nd observation deck was reopened on August 24, 2020. The closure of our Observatory and subsequent reopening under international, national, and local travel restrictions and quarantines caused us during the quarter to choose to perform an impairment test related to goodwill. We engaged a third-party valuation consulting firm to perform the valuation process. The analysis used a combination of the discounted cash flow method (a form of the income approach) utilizing Level 3 unobservable inputs and the guideline company method (a form of the market approach). Significant assumptions under the former included revenue and cost projections, weighted average cost of capital, long-term growth rate and income tax considerations while the latter included guideline company enterprise values, revenue multiples and control premium rates. Our methodology to review goodwill impairment, which included a significant amount of judgment and estimates, provided a reasonable basis to determine whether impairment had occurred. Based upon the results of the goodwill impairment test of the standalone Observatory reporting unit, which is after the intercompany rent expense paid to the Real Estate reporting unit, we

Debt

Debt	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Debt	Debt Debt consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): Principal Balance As of March 31, 2021 March 31, 2021 December 31, 2020 Stated Effective (1) Maturity (2) Mortgage debt collateralized by: Fixed rate mortgage debt Metro Center $ 86,803 $ 87,382 3.59 % 3.68 % 11/5/2024 10 Union Square 50,000 50,000 3.70 % 3.97 % 4/1/2026 1542 Third Avenue 30,000 30,000 4.29 % 4.53 % 5/1/2027 First Stamford Place (3) 180,000 180,000 4.28 % 4.71 % 7/1/2027 1010 Third Avenue and 77 West 55th Street 37,278 37,477 4.01 % 4.23 % 1/5/2028 250 West 57th Street 180,000 180,000 2.83 % 3.19 % 12/1/2030 10 Bank Street 31,795 32,025 4.23 % 4.36 % 6/1/2032 383 Main Avenue 30,000 30,000 4.44 % 4.55 % 6/30/2032 1333 Broadway 160,000 160,000 4.21 % 4.29 % 2/5/2033 Total mortgage debt 785,876 786,884 Senior unsecured notes: (4) Series A 100,000 100,000 3.93 % 3.96 % 3/27/2025 Series B 125,000 125,000 4.09 % 4.12 % 3/27/2027 Series C 125,000 125,000 4.18 % 4.21 % 3/27/2030 Series D 115,000 115,000 4.08 % 4.11 % 1/22/2028 Series E 160,000 160,000 4.26 % 4.27 % 3/22/2030 Series F 175,000 175,000 4.44 % 4.45 % 3/22/2033 Series G 100,000 100,000 3.61 % 4.89 % 3/17/2032 Series H 75,000 75,000 3.73 % 5.00 % 3/17/2035 Unsecured term loan facility (4) 215,000 215,000 LIBOR plus 1.20% 3.56 % 3/19/2025 Unsecured revolving credit facility (4) — — LIBOR plus 1.30% — 3/31/2025 Unsecured term loan facility (4) 175,000 175,000 LIBOR plus 1.50% 3.60 % 12/31/2026 Total principal 2,150,876 2,151,884 Deferred financing costs, net (14,575) (15,235) Total $ 2,136,301 $ 2,136,649 ______________ (1) The effective rate is the yield as of March 31, 2021 and includes the stated interest rate, deferred financing cost amortization and interest associated with variable to fixed interest rate swap agreements. (2) Pre-payment is generally allowed for each loan upon payment of a customary pre-payment penalty. (3) Represents a $164 million mortgage loan bearing interest at 4.09% and a $16 million loan bearing interest at 6.25%. (4) At March 31, 2021, we were in compliance with all debt covenants. Principal Payments Aggregate required principal payments at March 31, 2021 are as follows (amounts in thousands): Year Amortization Maturities Total 2021 $ 3,082 $ — $ 3,082 2022 5,628 — 5,628 2023 7,876 — 7,876 2024 7,958 77,675 85,633 2025 5,826 315,000 320,826 Thereafter 20,084 1,707,747 1,727,831 Total $ 50,454 $ 2,100,422 $ 2,150,876 Deferred Financing Costs Deferred financing costs, net, consisted of the following at March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Financing costs $ 42,689 $ 35,365 Less: accumulated amortization (19,202) (17,998) Total deferred financing costs, net $ 23,487 $ 17,367 Amortization expense related to deferred financing costs was $1.2 million and $0.9 million for the three months ended March 31, 2021 and 2020, respectively. Unsecured Revolving Credit and Term Loan Facilities On March 31, 2021, through our Operating Partnership, we entered into a second amendment to an existing credit agreement ("Amended Credit Agreement") that will govern an amended senior unsecured credit facility (the “Credit Facility”) with Bank of America, N.A., as administrative agent, and Bank of America, Wells Fargo Bank, National Association, Capital One, National Association and JPMorgan Chase Bank, N.A., as co-syndication agents, and the lenders and the letter of credit issuers party thereto. The Amended Credit Agreement amends the amended and restated credit agreement dated August 29, 2017, as amended, by and among the parties named therein. The Credit Facility is in the initial maximum principal amount of up to $1.065 billion, which consists of a $850.0 million revolving credit facility and a $215.0 million term loan facility. We borrowed the term loan facility in full in August 2017. We may request the Credit Facility be increased through one or more increases in the revolving credit facility or one or more increases in the term loan facility or the addition of new pari passu term loan tranches, for a maximum aggregate principal amount not to exceed $1.50 billion. The Credit Facility will be used for our working capital needs and for other general corporate purposes. As of March 31, 2021, we had no borrowings under the revolving credit facility and $215.0 million under the term loan facility. The revolving credit facility matures on March 31, 2025. We have the option to extend the initial term for up to two additional 6-month periods, subject to certain conditions, including the payment of an extension fee equal to 0.0625% and 0.075% of the then outstanding commitments under the revolving credit facility on the first and the second extensions, respectively. T he term loan facility matures on March 19, 2025. We may prepay the loans under the Credit Facility at any time in whole or in part, subject to reimbursement of the lenders’ breakage and redeployment costs in the case of prepayment of Eurodollar Rate borrowings. On March 19, 2020, we entered into a senior unsecured term loan facility (the “Term Loan Facility”) with Wells Fargo Bank, National Association, as administrative agent, Wells Fargo Securities, LLC as sole bookrunner, Wells Fargo Securities, LLC, Capital One, National Association, U.S. Bank National Association and SunTrust Robinson Humphrey, Inc. as Joint Lead Arrangers, Capital One, National Association, as syndication agent, U.S. Bank National Association and Truist Bank, as documentation agents, and the lenders party thereto. The Term Loan Facility is in the original principal amount of $175 million which we borrowed in full at closing. We may request the Term Loan Facility be increased through one or more increases or the addition of new pari passu term loan tranches, for a maximum aggregate principal amount not to exceed $225 million. As of March 31, 2021, our borrowings amounted to $175.0 million under the Term Loan Facility. The Term Loan Facility matures on December 31, 2026. We may prepay loans under the Term Loan Facility at any time in whole or in part, subject to reimbursement of the lenders’ breakage and redeployment costs in the case of prepayment of Eurodollar rate borrowings and, if the prepayment occurs on or before December 31, 2021, a prepayment fee. If the prepayment occurs after December 31, 2020 but on or prior to December 31, 2021, the prepayment fee is equal to 1.0% of the principal amount prepaid. The terms of both the Credit Facility and the Term Loan Facility include customary covenants, including limitations on liens, investment, distributions, debt, fundamental changes, and transactions with affiliates and require certain customary financial reports. It also requires compliance with financial ratios including a maximum leverage ratio, a maximum secured leverage ratio, a minimum fixed charge coverage ratio, a minimum unencumbered interest coverage ratio, and a maximum unsecured leverage ratio. The agreement also contains customary events of default (subject in certain cases to specified cure periods), including but not limited to non-payment, breach of covenants, representations or warranties, cross defaults, bankruptcy or other insolvency events, judgments, ERISA events, invalidity of loan documents, loss of real estate investment trust qualification, and occurrence of a change of control. As of March 31, 2021, we were in compliance with the covenants under the Credit Facility and the Term Loan Facility. Senior Unsecured Notes On March 17, 2020, through the Operating Partnership, we entered into an agreement to issue and sell an aggregate $175 million of senior unsecured notes, consisting of (a) $100 million aggregate principal amount of 3.61% Series G Senior Notes due March 17, 2032 (the “Series G Notes”) and (b) $75 million aggregate principal amount of 3.73% Series H Senior Notes due March 17, 2035 (the “Series H Notes”). The issue price for the Series G and H Notes was 100% of the aggregate principal amount thereof. The terms of the Series G and H Notes agreement include customary covenants, including limitations on liens, investment, distributions, debt, fundamental changes, and transactions with affiliates and require certain customary financial reports. It also requires compliance with financial ratios including a maximum leverage ratio, a maximum secured leverage ratio, a minimum fixed charge coverage ratio, a minimum unencumbered interest coverage ratio, and a maximum unsecured leverage ratio. The agreement also contains customary events of default (subject in certain cases to specified cure periods), including but not limited to non-payment, breach of covenants, representations or warranties, cross defaults, bankruptcy or other insolvency events, judgments, ERISA events, the occurrence of certain change of control transactions and loss of real estate investment trust qualification. As of March 31, 2021, we were in compliance with the covenants under the outstanding senior unsecured notes.

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	3 Months Ended
	Mar. 31, 2021
Payables and Accruals [Abstract]
Accounts Payable and Accrued Expenses	Accounts Payable and Accrued Expenses Accounts payable and accrued expenses consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Accrued capital expenditures $ 60,536 $ 58,057 Accounts payable and accrued expenses 30,032 32,309 Interest rate swap agreements liability 7,450 8,849 Accrued interest payable 3,436 3,219 Due to affiliated companies 927 769 Total accounts payable and accrued expenses $ 102,381 $ 103,203

Financial Instruments and Fair

Financial Instruments and Fair Values	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Values	Financial Instruments and Fair Values Derivative Financial Instruments We use derivative financial instruments primarily to manage interest rate risk and such derivatives are not considered speculative. These derivative instruments are typically in the form of interest rate swap and forward agreements and the primary objective is to minimize interest rate risks associated with investing and financing activities. The counterparties of these arrangements are major financial institutions with which we may also have other financial relationships. We are exposed to credit risk in the event of non-performance by these counterparties; however, we currently do not anticipate that any of the counterparties will fail to meet their obligations. We have agreements with our derivative counterparties that contain a provision where if we either default or are capable of being declared in default on any of our indebtedness, then we could also be declared in default on our derivative obligations. As of March 31, 2021, the fair value of the derivative in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to the agreement was $7.5 million. If we had breached any of these provisions at March 31, 2021, we could have been required to settle our obligation under the agreement at its termination value of $7.5 million. As of March 31, 2021 and December 31, 2020, we had an interest rate LIBOR swap with an aggregate notional value of $265.0 million and $265.0 million, respectively. The notional value does not represent exposure to credit, interest rate or market risks. As of March 31, 2021 and December 31, 2020, the fair value of our derivative instrument amounted to $(7.5) million and $(8.8) million, respectively, which is included in accounts payable and accrued expenses on the condensed consolidated balance sheets. This interest rate swap has been designated as a cash flow hedge and hedges the variability in future cash flows associated with our existing variable-rate term loan facilities. As of March 31, 2021 and 2020, our cash flow hedge is deemed highly effective and a net unrealized gain (loss) of $2.9 million and $(16.9) million for the three months ended March 31, 2021 and 2020, respectively, relating to both active and terminated hedges of interest rate risk, are reflected in the condensed consolidated statements of comprehensive income. Amounts reported in accumulated other comprehensive income (loss) related to derivatives will be reclassified to interest expense as interest payments are made on the debt. We estimate that $(11.5) million net loss of the current balance held in accumulated other comprehensive income (loss) will be reclassified into interest expense within the next 12 months. The table below summarizes the terms of agreements and the fair values of our derivative financial instruments as of March 31, 2021 and December 31, 2020 (dollar amounts in thousands): March 31, 2021 December 31, 2020 Derivative Notional Amount Receive Rate Pay Rate Effective Date Expiration Date Asset Liability Asset Liability Interest rate swap $ 265,000 1 Month LIBOR 2.1485% August 31, 2017 August 24, 2022 $ — $ (7,450) $ — $ (8,849) The table below shows the effect of our derivative financial instruments designated as cash flow hedges on accumulated other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 (amounts in thousands): Three Months Ended Effects of Cash Flow Hedges March 31, 2021 March 31, 2020 Amount of gain (loss) recognized in other comprehensive income (loss) $ 59 $ (17,695) Amount of gain (loss) reclassified from accumulated other comprehensive (loss) into interest expense (2,869) (796) The table below shows the effect of our derivative financial instruments designated as cash flow hedges on the condensed consolidated statements of operations for the three months ended March 31, 2021 and 2020 (amounts in thousands): Three Months Ended Effects of Cash Flow Hedges March 31, 2021 March 31, 2020 Total interest (expense) presented in the condensed consolidated statements of operations in which the effects of cash flow hedges are recorded $ (23,554) $ (19,618) Amount of gain (loss) reclassified from accumulated other comprehensive (loss) into interest expense (2,869) (796) Fair Valuation The estimated fair values at March 31, 2021 and December 31, 2020 were determined by management, using available market information and appropriate valuation methodologies. Considerable judgment is necessary to interpret market data and develop estimated fair value. Accordingly, the estimates presented herein are not necessarily indicative of the amounts we could realize on disposition of the financial instruments. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. The fair value of derivative instruments is determined using widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. Although the majority of the inputs used to value our derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with our derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by ourselves and our counterparties. The impact of such credit valuation adjustments, determined based on the fair value of each individual contract, was not significant to the overall valuation. As a result, all of our derivatives were classified as Level 2 of the fair value hierarchy. The fair value of our mortgage notes payable, senior unsecured notes - Series A, B, C, D, E, F, G and H, unsecured term loan facilities, unsecured revolving credit facility and ground lease liabilities which are determined using Level 3 inputs, are estimated by discounting the future cash flows using current interest rates at which similar borrowings could be made to us. The following tables summarize the carrying and estimated fair values of our financial instruments as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 Estimated Fair Value Carrying Total Level 1 Level 2 Level 3 Interest rate swap included in accounts payable and accrued expenses $ 7,450 $ 7,450 $ — $ 7,450 $ — Mortgage notes payable 775,276 772,147 — — 772,147 Senior unsecured notes - Series A, B, C, D, E, F, G and H 973,214 986,839 — — 986,839 Unsecured term loan facilities 387,811 390,000 — — 390,000 December 31, 2020 Estimated Fair Value Carrying Total Level 1 Level 2 Level 3 Interest rate swap included in accounts payable and accrued expenses $ 8,849 $ 8,849 $ — $ 8,849 $ — Mortgage notes payable 775,929 808,294 — — 808,294 Senior unsecured notes - Series A, B, C, D, E, F, G and H 973,159 1,039,857 — — 1,039,857 Unsecured term loan facilities 387,561 390,000 — — 390,000 Disclosure about the fair value of financial instruments is based on pertinent information available to us as of March 31, 2021 and December 31, 2020. Although we are not aware of any factors that would significantly affect the reasonable fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since that date and current estimates of fair value may differ significantly from the amounts presented herein.

Leases

Leases	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Leases	Leases Lessor We lease various spaces to tenants over terms ranging from one Rental revenue includes fixed and variable payments. Fixed payments primarily relate to base rent and variable payments primarily relate to tenant expense reimbursements for certain property operating costs. The components of rental revenue for the three months ended March 31, 2021 and 2020 are as follows (amounts in thousands): Three Months Ended Rental revenue March 31, 2021 March 31, 2020 Fixed payments $ 125,773 $ 130,514 Variable payments 14,458 17,599 Total rental revenue $ 140,231 $ 148,113 As of March 31, 2021, we were entitled to the following future contractual minimum lease payments (excluding operating expense reimbursements) on non-cancellable operating leases to be received which expire on various dates through 2038 (amounts in thousands): Remainder of 2021 $ 369,719 2022 490,994 2023 471,638 2024 435,036 2025 396,144 Thereafter 1,859,648 $ 4,023,179 The above future minimum lease payments exclude tenant recoveries, amortization of deferred rent receivables and the net accretion of above-below-market lease intangibles. Some leases are subject to termination options generally upon payment of a termination fee. The preceding table is prepared assuming such options are not exercised. Lessee We determine if an arrangement is a lease at inception. Our operating lease agreements relate to three ground lease assets and are reflected in right-of-use assets of $29.1 million and lease liabilities of $29.1 million in our consolidated balance sheet as of March 31, 2021. Right-of-use assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Right-of-use assets and liabilities are recognized at the commencement date based on the present value of lease payments over the lease term. Variable lease payments are excluded from the right-of-use assets and lease liabilities and are recognized in the period in which the obligation for those payments is incurred. We make payments under ground leases related to three of our properties. The ground leases are due to expire between the years 2050 and 2077, inclusive of extension options, and have no variable payments or residual value guarantees. As our leases do not provide an implicit rate, we determined our incremental borrowing rate based on information available at the date of adoption of ASU No. 2016-02, Leases (Topic 842), in determining the present value of lease payments. The weighted average incremental borrowing rate used to calculate the right-of-use assets and lease liabilities as of March 31, 2021 was 4.5%. Rent expense for lease payments related to our operating leases is recognized on a straight-line basis over the non-cancellable term of the leases. The weighted average remaining lease term as of March 31, 2021 was 49.1 years. As of March 31, 2021, the following table summarizes our future minimum lease payments discounted by our incremental borrowing rates to calculate the lease liabilities of our leases (amounts in thousands): Remainder of 2021 $ 1,139 2022 1,518 2023 1,518 2024 1,518 2025 1,518 Thereafter 65,262 Total undiscounted cash flows 72,473 Present value discount (43,422) Ground lease liabilities $ 29,051
Leases	Leases Lessor We lease various spaces to tenants over terms ranging from one Rental revenue includes fixed and variable payments. Fixed payments primarily relate to base rent and variable payments primarily relate to tenant expense reimbursements for certain property operating costs. The components of rental revenue for the three months ended March 31, 2021 and 2020 are as follows (amounts in thousands): Three Months Ended Rental revenue March 31, 2021 March 31, 2020 Fixed payments $ 125,773 $ 130,514 Variable payments 14,458 17,599 Total rental revenue $ 140,231 $ 148,113 As of March 31, 2021, we were entitled to the following future contractual minimum lease payments (excluding operating expense reimbursements) on non-cancellable operating leases to be received which expire on various dates through 2038 (amounts in thousands): Remainder of 2021 $ 369,719 2022 490,994 2023 471,638 2024 435,036 2025 396,144 Thereafter 1,859,648 $ 4,023,179 The above future minimum lease payments exclude tenant recoveries, amortization of deferred rent receivables and the net accretion of above-below-market lease intangibles. Some leases are subject to termination options generally upon payment of a termination fee. The preceding table is prepared assuming such options are not exercised. Lessee We determine if an arrangement is a lease at inception. Our operating lease agreements relate to three ground lease assets and are reflected in right-of-use assets of $29.1 million and lease liabilities of $29.1 million in our consolidated balance sheet as of March 31, 2021. Right-of-use assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Right-of-use assets and liabilities are recognized at the commencement date based on the present value of lease payments over the lease term. Variable lease payments are excluded from the right-of-use assets and lease liabilities and are recognized in the period in which the obligation for those payments is incurred. We make payments under ground leases related to three of our properties. The ground leases are due to expire between the years 2050 and 2077, inclusive of extension options, and have no variable payments or residual value guarantees. As our leases do not provide an implicit rate, we determined our incremental borrowing rate based on information available at the date of adoption of ASU No. 2016-02, Leases (Topic 842), in determining the present value of lease payments. The weighted average incremental borrowing rate used to calculate the right-of-use assets and lease liabilities as of March 31, 2021 was 4.5%. Rent expense for lease payments related to our operating leases is recognized on a straight-line basis over the non-cancellable term of the leases. The weighted average remaining lease term as of March 31, 2021 was 49.1 years. As of March 31, 2021, the following table summarizes our future minimum lease payments discounted by our incremental borrowing rates to calculate the lease liabilities of our leases (amounts in thousands): Remainder of 2021 $ 1,139 2022 1,518 2023 1,518 2024 1,518 2025 1,518 Thereafter 65,262 Total undiscounted cash flows 72,473 Present value discount (43,422) Ground lease liabilities $ 29,051

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings Except as described below, as of March 31, 2021, we were not involved in any material litigation, nor, to our knowledge, was any material litigation threatened against us or our properties, other than routine litigation arising in the ordinary course of business such as disputes with tenants. We believe that the costs and related liabilities, if any, which may result from such actions will not materially affect our condensed consolidated financial position, operating results or liquidity. As previously disclosed, in October 2014, 12 former investors (the "Claimants") in Empire State Building Associates L.L.C. (“ESBA”), which prior to the initial public offering of our company (the "Offering"), owned the fee title to the Empire State Building, filed an arbitration with the American Arbitration Association against Peter L. Malkin, Anthony E. Malkin, Thomas N. Keltner, Jr., and our subsidiary ESRT MH Holdings LLC, the former supervisor of ESBA (the "Respondents"). The statement of claim (also filed later in federal court in New York for the expressed purpose of tolling the statute of limitations) alleges breach of fiduciary duty and related claims in connection with the Offering and formation transactions and seeks monetary damages and declaratory relief. Claimants had opted out of a prior class action bringing similar claims that was settled with court approval. Respondents filed an answer and counterclaims. In March 2015, the federal court action was stayed on consent of all parties pending the arbitration. Arbitration hearings started in May 2016 and concluded in August 2018. On August 26, 2020, the arbitration panel issued an award that denied all Claimants’ claims with one exception, on which it awarded Claimants approximately $1.2 million, inclusive of seven years of interest through October 2, 2020. This amount was recorded as an IPO litigation expense in the consolidated statement of operations for the year ended December 31, 2020. Respondents believe that such award in favor of the Claimants is entirely without merit, and have sought vacatur of that portion of the award. In addition, certain of the Claimants in the federal court action sought to pursue claims in that case against Respondents. Respondents believe that any such claims are meritless. The magistrate judge assigned to the action has issued a Report and Recommendation rejecting Claimants’ claims; the district judge will decide whether to adopt the Report and Recommendation. Pursuant to indemnification agreements which were made with our directors, executive officers and chairman emeritus as part of our formation transactions, Anthony E. Malkin, Peter L. Malkin and Thomas N. Keltner, Jr. have defense and indemnity rights from us with respect to this arbitration. Unfunded Capital Expenditures At March 31, 2021, we estimate that we will incur approximately $99.3 million of capital expenditures (including tenant improvements and leasing commissions) on our properties pursuant to existing lease agreements. We expect to fund these capital expenditures with operating cash flow, additional property level mortgage financings, our unsecured credit facility, cash on hand and other borrowings. Future property acquisitions may require substantial capital investments for refurbishment and leasing costs. We expect that these financing requirements will be met in a similar fashion. Concentration of Credit Risk Financial instruments that subject us to credit risk consist primarily of cash and cash equivalents, restricted cash, short-term investments, tenant and other receivables and deferred rent receivables. At March 31, 2021, we held on deposit at various major financial institutions cash and cash equivalents and restricted cash balances in excess of amounts insured by the Federal Deposit Insurance Corporation. Asset Retirement Obligations We are required to accrue costs that we are legally obligated to incur on retirement of our properties which result from acquisition, construction, development and/or normal operation of such properties. Retirement includes sale, abandonment or disposal of a property. Under that standard, a conditional asset retirement obligation represents a legal obligation to perform an asset retirement activity in which the timing and/or method of settlement is conditional on a future event that may or may not be within a company’s control and a liability for a conditional asset retirement obligation must be recorded if the fair value of the obligation can be reasonably estimated. Environmental site assessments and investigations have identified asbestos or asbestos-containing building materials in certain of our properties. As of March 31, 2021, management has no plans to remove or alter these properties in a manner that would trigger federal and other applicable regulations for asbestos removal, and accordingly, the obligations to remove the asbestos or asbestos-containing building materials from these properties have indeterminable settlement dates. As such, we are unable to reasonably estimate the fair value of the associated conditional asset retirement obligation. However, ongoing asbestos abatement, maintenance programs and other required documentation are carried out as required and related costs are expensed as incurred. Other Environmental Matters Certain of our properties have been inspected for soil contamination due to pollutants, which may have occurred prior to our ownership of these properties or subsequently in connection with its development and/or its use. Required remediation to such properties has been completed, and as of March 31, 2021, management believes that there are no obligations related to environmental remediation other than maintaining the affected sites in conformity with the relevant authority’s mandates and filing the required documents. All such maintenance costs are expensed as incurred. We expect that resolution of the environmental matters relating to the above will not have a material impact on our business, assets, consolidated financial condition, results of operations or liquidity. However, we cannot be certain that we have identified all environmental liabilities at our properties, that all necessary remediation actions have been or will be undertaken at our properties or that we will be indemnified, in full or at all, in the event that such environmental liabilities arise. Insurance Coverage

Equity

Equity	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Equity	Equity Shares and Units An operating partnership unit of the Operating Partnership ("OP Unit") and a share of our common stock have essentially the same economic characteristics as they receive the same per unit profit distributions of the Operating Partnership. On the one-year anniversary of issuance, an OP Unit may be tendered for redemption for cash; however, we have sole and absolute discretion, and sufficient authorized common stock, to exchange OP Units for shares of common stock on a one-for-one basis instead of cash. On May 16, 2019, the Empire State Realty Trust, Inc. Empire State Realty OP, L.P. 2019 Equity Incentive Plan (“2019 Plan”) was approved by our shareholders. The 2019 Plan provides for grants to directors, employees and consultants of our company and operating partnership, including options, restricted stock, restricted stock units, stock appreciation rights, performance awards, dividend equivalents and other equity-based awards. An aggregate of approximately 11.0 million shares of our common stock are authorized for issuance under awards granted pursuant to the 2019 Plan. We will not issue any new equity awards under the First Amended and Restated Empire State Realty Trust, Inc. and Empire State Realty OP, L.P. 2013 Equity Incentive Plan ("2013 Plan", and collectively with the 2019 Plan, "the Plans"). The shares of Class A common stock underlying any awards under the 2019 Plan and the 2013 Plan that are forfeited, canceled or otherwise terminated, other than by exercise, will be added back to the shares of Class A common stock available for issuance under the 2019 Plan. Shares tendered or held back upon exercise of a stock option or settlement of an award under the 2019 Plan or the 2013 Plan to cover the exercise price or tax withholding and shares subject to a stock appreciation right that are not issued in connection with the stock settlement of the stock appreciation right upon exercise thereof, will not be added back to the shares of Class A common stock available for issuance under the 2019 Plan. In addition, shares of Class A common stock repurchased on the open market will not be added back to the shares of Class A common stock available for issuance under the 2019 Plan. Long-term incentive plan ("LTIP") units are a special class of partnership interests in the Operating Partnership. Each LTIP unit awarded will be deemed equivalent to an award of one share of stock under the Plans, reducing the availability for other equity awards on a one-for-one basis. The vesting period for LTIP units, if any, will be determined at the time of issuance. Under the terms of the LTIP units, the Operating Partnership will revalue for tax purposes its assets upon the occurrence of certain specified events, and any increase in valuation from the time of grant until such event will be allocated first to the holders of LTIP units to equalize the capital accounts of such holders with the capital accounts of OP unitholders. Subject to any agreed upon exceptions, once vested and having achieved parity with OP unitholders, LTIP units are convertible into OP Units in the Operating Partnership on a one-for-one basis. LTIP units subject to time-based vesting, whether vested or not, receive the same per unit distributions as OP units, which equal per share dividends (both regular and special) on our common stock. LTIP units subject to market-based vesting receive 10% of such distributions currently, unless and until such LTIP units are earned based on performance, at which time they will receive the accrued and unpaid 90% and will commence receiving 100% of such distributions thereafter. The following is net income attributable to common stockholders and the issuance of our Class A shares in exchange for the conversion of OP Units into common stock (amounts in thousands): Three Months Ended March 31, 2021 March 31, 2020 Net income (loss) attributable to common stockholders $ (2,621) $ 4,495 Increase in additional paid-in capital for the conversion of OP Units into common stock 2,689 7,661 Change from net income (loss) attributable to common stockholders and transfers from non-controlling interests $ 68 $ 12,156 As of March 31, 2021, there were 285,622,197 common stock and OP Units outstanding, of which 172,331,871, or 60.3%, were owned by us and 113,290,326, or 39.7%, were owned by other partners, including certain directors, officers and other members of executive management. Stock and Publicly Traded Operating Partnership Unit Repurchase Program Our Board of Directors reauthorized the repurchase of up to $500 million of our Class A common stock and the Operating Partnership’s Series ES, Series 250 and Series 60 operating partnership units through December 31, 2021. Under the program, we may purchase our Class A common stock and the Operating Partnership’s Series ES, Series 250 and Series 60 operating partnership units in accordance with applicable securities laws from time to time in the open market or in privately negotiated transactions. The timing, manner, price and amount of any repurchases will be determined by us at our discretion and will be subject to stock price, availability, trading volume and general market conditions. The authorization does not obligate us to acquire any particular amount of securities, and the program may be suspended or discontinued at our discretion without prior notice. The following table summarizes our purchases of equity securities each of the three months ended March 31, 2021: Period Total Number of Shares Purchased Weighted Average Price Paid per Share Total Number of Shares Purchased as Part of Publicly Announced Plan Maximum Approximate Dollar Value Available for Future Purchase (in thousands) January 2021 337,339 $ 9.17 337,339 $ 496,908 February 2021 45,732 $ 9.65 45,732 $ 496,467 March 2021 — $ — — $ 496,467 Private Perpetual Preferred Units As of March 31, 2021, there were 4,664,038 Series 2019 Preferred Units ("Series 2019 Preferred Units") and 1,560,360 Series 2014 Private Perpetual Preferred Units ("Series 2014 Preferred Units"). The Series 2019 Preferred Units have a liquidation preference of $13.52 per unit and are entitled to receive cumulative preferential annual cash distributions of $0.70 per unit payable in arrears on a quarterly basis. The Series 2019 Preferred Units are not redeemable at the option of the holders and are redeemable at our option only in the case of specific defined events. The Series 2014 Preferred Units which have a liquidation preference of $16.62 per unit and are entitled to receive cumulative preferential annual cash distributions of $0.60 per unit payable in arrears on a quarterly basis. The Series 2014 Preferred Units are not redeemable at the option of the holders and are redeemable at our option only in the case of specific defined events. Dividends and Distributions Total dividends paid to common stockholders were $0.0 million and $19.0 million for the three months ended March 31, 2021 and 2020, respectively. Total distributions paid to OP unitholders, excluding inter-company distributions, were $0.0 million and $12.6 million for the three months ended March 31, 2021 and 2020, respectively. Total distributions paid to preferred unitholders were $1.1 million and $1.1 million for the three months ended March 31, 2021 and 2020, respectively. Incentive and Share-Based Compensation The Plans provide for grants to directors, employees and consultants consisting of stock options, restricted stock, dividend equivalents, stock payments, performance shares, LTIP units, stock appreciation rights and other incentive awards. An aggregate of 11.0 million shares of our common stock is authorized for issuance under awards granted pursuant to the 2019 Plan, and as of March 31, 2021, 7.8 million shares of common stock remain available for future issuance. In March 2021, we made grants of LTIP units to executive officers under the 2019 Plan. At such time, we granted to executive officers a total of 364,199 LTIP units that are subject to time-based vesting and 1,007,156 LTIP units that are subject to market-based vesting, with fair market values of $3.4 million for the time-based vesting awards and $6.9 million for the market-based vesting awards. In March 2021, we made grants of LTIP units and restricted stock to certain other employees under the 2019 Plan. At such time, we granted to certain other employees a total of 128,419 LTIP units and 113,333 shares of restricted stock that are subject to time-based vesting and 192,760 LTIP units that are subject to market-based vesting, with fair market values of $2.7 million for the time-based vesting awards and $1.5 million for the market-based vesting awards. The awards subject to time-based vesting vest ratably over four years from January 1, 2021, subject generally to the grantee's continued employment. The first installment vests on January 1, 2022 and the remainder will vest thereafter in three equal annual installments. The vesting of the LTIP units subject to market-based vesting is based on the achievement of relative total stockholder return hurdles over a three-year performance period, commencing on January 1, 2021. Following the completion of the three-year performance period, our Compensation and Human Capital Committee will determine the number of LTIP units to which the grantee is entitled based on our performance relative to the performance hurdles set forth in the LTIP unit award agreements the grantee entered into in connection with the award grant. These units then vest in two installments, with the first installment vesting on January 1, 2024 and the second installment vesting on January 1, 2025, subject generally to the grantee's continued employment on those dates. In March 2021, we also made one-time additional grants of LTIP units and restricted stock to an executive officer and certain other employees under the 2019 Plan. At such time, we granted the executive officer 46,168 LTIP units that are subject to time-based vesting and we granted to certain other employees 85,409 LTIP units and 7,562 restricted stock that are subject to time-based vesting, with fair market values of $1.5 million. These awards are subject to time-based vesting and vest over five years from January 1, 2021, subject generally to the grantee's continued employment. The first installment vests 30% on January 1, 2024, the second installment vests 30% on January 1, 2025 and the remainder of 40% will vest on January 1, 2026. For awards granted in 2017, 2018, 2019 and 2020, our named executive officers can elect to receive their annual incentive bonus in any combination of (i) cash or vested LTIPs at the face amount of such bonus or (ii) time-vesting LTIPs which would vest over three years, subject to continued employment, at 125% of such face amount. For awards granted in 2021, the amounts vest at 120% of such face amount. In March 2021, we made grants of LTIP units to executive officers under the 2019 Plan in connection with the 2020 bonus election program. We granted to executive officers a total of 235,729 LTIP units that are subject to time-based vesting with a fair market value of $2.2 million. Of these LTIP units, 39,472 LTIP units vested immediately on the grant date and 196,257 LTIP units vest ratably over three years from January 1, 2021, subject generally to the grantee's continued employment. The first installment vests on January 1, 2022 and the remainder will vest thereafter in two equal annual installments. In March 2020, we made grants of LTIP units to executive officers under the 2019 Plan. At such time, we granted to executive officers a total of 745,155 LTIP units that are subject to time-based vesting and 3,358,767 LTIP units that are subject to market-based vesting, with fair market values of $5.6 million for the time-based vesting awards and $14.0 million for the market-based vesting awards. In March 2020, we made grants of LTIP units and restricted stock to certain other employees under the 2019 Plan. At such time, we granted to certain other employees a total of 113,971 LTIP units and 158,806 shares of restricted stock that are subject to time-based vesting and 502,475 LTIP units that are subject to market-based vesting, with fair market values of $2.3 million for the time-based vesting awards and $2.3 million for the market-based vesting awards. The awards subject to time-based vesting vest ratably over four years from January 1, 2020, subject generally to the grantee's continued employment. The first installment vests on January 1, 2021 and the remainder will vest thereafter in three equal annual installments. The vesting of the LTIP units subject to market-based vesting is based on the achievement of relative total stockholder return hurdles over a three-year performance period, commencing on January 1, 2020. Following the completion of the three-year performance period, our Compensation and Human Capital Committee will determine the number of LTIP units to which the grantee is entitled based on our performance relative to the performance hurdles set forth in the LTIP unit award agreements the grantee entered into in connection with the award grant. These units then vest in two installments, with the first installment vesting on January 1, 2023 and the second installment vesting on January 1, 2024, subject generally to the grantee's continued employment on those dates. In March 2020, we made grants of LTIP units to executive officers under the 2019 Plan in connection with the 2019 bonus election program. We granted to executive officers a total of 624,380 LTIP units that are subject to time-based vesting with a fair market value of $4.4 million. Of these LTIP units, 23,049 LTIP units vested immediately on the grant date and 601,331 LTIP units vest ratably over three years from January 1, 2020, subject generally to the grantee's continued employment. The first installment vests on January 1, 2021 and the remainder will vest thereafter in two equal annual installments. In May 2020, we made grants of LTIP units under the 2019 Plan. At such time, we granted our non-employee directors a total of 171,153 LTIP units that are subject to time-based vesting with fair market values of $1.1 million. These awards vest ratably over three years from the date of the grant, subject generally to the director's continued service on our Board of Directors. We also granted Christina Chiu, our Executive Vice President and Chief Financial Officer, a total of 82,199 LTIP units that are subject to time-based vesting and 116,927 LTIP units that are subject to market-based vesting, with fair market values of $0.5 million for the time-based vesting awards and $0.5 million for the market-based vesting awards. We also granted certain other employees a total of 63,229 LTIP units that are subject to time-based vesting with a fair market value of $0.4 million. The awards subject to time-based vesting vest ratably over three In December and August 2020, we granted Grant H. Hill and R. Paige Hood, respectively, our new non-employee directors, a total of 31,117 LTIP units that are subject to time-based vesting with a fair market value of $0.2 million. These awards vest ratably on each of the first three anniversaries of May 15, 2020, subject generally to their continued service on our Board of Directors. In COVID-19 disrupted markets during the first quarter of 2020, the LTIP units that are subject to market-based vesting were undervalued on initial appraisal, and the resulting number of LTIP units issued in March 2020 was reduced on final appraisal to match the original Board-approved dollar value. In June 2020, we reduced the grants of LTIP units that are subject to market-based vesting which were awarded to executive officers and certain other employees by 666,933 LTIP units with fair market values of $2.8 million and 99,630 LTIP units with fair market values of $0.5 million, respectively. Share-based compensation for time-based equity awards is measured at the fair value of the award on the date of grant and recognized as an expense on a straight-line basis over the shorter of (i) the stated vesting period, which is generally three four three For the market-based LTIP units, the fair value of the awards was estimated using a Monte Carlo Simulation model and discounted for the restriction period during which the LTIP units cannot be redeemed or transferred and the uncertainty regarding if, and when, the book capital account of the LTIP units will equal that of the common units. Our stock price, along with the prices of the comparative indexes, is assumed to follow the Geometric Brownian Motion Process. Geometric Brownian Motion is a common assumption when modeling in financial markets, as it allows the modeled quantity (in this case the stock price) to vary randomly from its current value and take any value greater than zero. The volatilities of the returns on our stock price and the comparative indexes were estimated based on implied volatilities and historical volatilities using a six-year look-back period. The expected growth rate of the stock prices over the performance period is determined with consideration of the risk-free rate as of the grant date. For LTIP unit awards that are time-based, the fair value of the awards was estimated based on the fair value of our stock at the grant date discounted for the restriction period during which the LTIP units cannot be redeemed or transferred and the uncertainty regarding if, and when, the book capital account of the LTIP units will equal that of the common units. For restricted stock awards, we estimate the stock compensation expense based on the fair value of the stock at the grant date. LTIP units and restricted stock issued during the three months ended March 31, 2021 were valued at $18.3 million. The weighted average per unit or share fair value was $8.38 for grants issued in 2021. The per unit or share granted in 2020 was estimated on the respective dates of grant using the following assumptions: an expected life from 2.0 to 5.3 years, a dividend rate of 2.60%, a risk-free interest rate from 0.12% to 0.32%, and an expected price volatility from 36.0% to 53.0%. No other stock options, dividend equivalents, or stock appreciation rights were issued or outstanding in 2021. The following is a summary of restricted stock and LTIP unit activity for the three months ended March 31, 2021: Restricted Stock LTIP Units Weighted Average Grant Fair Value Unvested balance at December 31, 2020 217,700 7,750,284 $ 6.94 Vested (70,338) (847,406) 11.94 Granted 120,895 2,059,840 8.38 Forfeited or unearned (9,495) (1,417,107) 5.47 Unvested balance at March 31, 2021 258,762 7,545,611 $ 7.02 The LTIP unit and restricted stock awards are treated for accounting purposes as immediately vested upon the later of (i) the date the grantee attains the age of 60 or 65, as applicable, and (ii) the date on which grantee has first completed ten years of continuous service with our company or its affiliates. For award agreements that qualify, we recognize noncash compensation expense on the grant date for the time-based awards and ratably over the vesting period for the performance-based awards, and accordingly, we recognized $1.0 million and $1.6 million for the three months ended March 31, 2021 and 2020, respectively. Unrecognized compensation expense was $2.1 million at March 31, 2021, which will be recognized over a weighted average period of 2.7 years. For the remainder of the LTIP unit and restricted stock awards, we recognize noncash compensation expense ratably over the vesting period, and accordingly, we recognized noncash compensation expense of $3.8 million and $4.3 million for the three months ended March 31, 2021 and 2020 respectively. Unrecognized compensation expense was $38.8 million at March 31, 2021, which will be recognized over a weighted average period of 2.7 years. Earnings Per Share Earnings per share for the three months ended March 31, 2021 and 2020 is computed as follows (amounts in thousands, except per share amounts): Three Months Ended March 31, 2021 March 31, 2020 Numerator - Basic: Net income (loss) $ (3,191) $ 8,288 Private perpetual preferred unit distributions (1,050) (1,050) Net income (loss) attributable to non-controlling interests 1,620 (2,743) Earnings allocated to unvested shares — (11) Net income (loss) attributable to common stockholders – basic $ (2,621) $ 4,484 Numerator - Diluted: Net income (loss) $ (3,191) $ 8,288 Private perpetual preferred unit distributions (1,050) (1,050) Earnings allocated to unvested shares — (11) Net income (loss) attributable to common stockholders – diluted $ (4,241) $ 7,227 Denominator: Weighted average shares outstanding – basic 171,735 181,741 Operating partnership units 106,146 110,904 Effect of dilutive securities: Stock-based compensation plans — — Weighted average shares outstanding – diluted 277,881 292,645 Earnings (loss) per share: Basic $ (0.02) $ 0.02 Diluted $ (0.02) $ 0.02 There were 315,595 and 399,894 antidilutive shares and LTIP units for the three months ended March 31, 2021 and 2020, respectively.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Supervisory Fee Revenue We earned supervisory fees from entities affiliated with Anthony E. Malkin, our Chairman and Chief Executive Officer, of $0.2 million and $0.2 million for the three months ended March 31, 2021 and 2020, respectively. These fees are included within third-party management and other fees. Property Management Fee Revenue We earned property management fees from entities affiliated with Anthony E. Malkin of $0.04 million and $0.1 million for the three months ended March 31, 2021 and 2020, respectively. These fees are included within third-party management and other fees.

Segment Reporting

Segment Reporting	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting We have identified two reportable segments: (1) real estate and (2) observatory. Our real estate segment includes all activities related to the ownership, management, operation, acquisition, redevelopment, repositioning and disposition of our traditional real estate assets. Our observatory segment includes the operation of the 86th and 102nd floor observatories at the Empire State Building. These two lines of businesses are managed separately because each business requires different support infrastructures, provides different services and has dissimilar economic characteristics such as investments needed, stream of revenues and marketing strategies. We account for intersegment sales and rent as if the sales or rent were to third parties, that is, at current market prices. The following tables provide components of segment net income (loss) for each segment for the three and three months ended March 31, 2021 and 2020 (amounts in thousands): Three Months Ended March 31, 2021 Real Estate Observatory Intersegment Elimination Total Revenues: Rental revenue $ 140,231 $ — $ — $ 140,231 Intercompany rental revenue 4,932 — (4,932) — Observatory revenue — 2,603 — 2,603 Lease termination fees 1,289 — — 1,289 Third-party management and other fees 276 — — 276 Other revenue and fees 905 — — 905 Total revenues 147,633 2,603 (4,932) 145,304 Operating expenses: Property operating expenses 30,279 — — 30,279 Intercompany rent expense — 4,932 (4,932) — Ground rent expense 2,331 — — 2,331 General and administrative expenses 13,853 — — 13,853 Observatory expenses — 4,588 — 4,588 Real estate taxes 31,447 — — 31,447 Depreciation and amortization 44,419 38 — 44,457 Total operating expenses 122,329 9,558 (4,932) 126,955 Total operating income (loss) 25,304 (6,955) — 18,349 Other income (expense): Interest income 120 2 — 122 Interest expense (23,554) — — (23,554) Loss on early extinguishment of debt (214) — — (214) Income (loss) before income taxes 1,656 (6,953) — (5,297) Income tax (expense) benefit (283) 2,389 — 2,106 Net income (loss) $ 1,373 $ (4,564) $ — $ (3,191) Segment assets $ 3,910,152 $ 241,371 $ — $ 4,151,523 Expenditures for segment assets $ 23,331 $ 4 $ — $ 23,335 Three Months Ended March 31, 2020 Real Estate Observatory Intersegment Elimination Total Revenues: Rental revenue $ 148,113 $ — $ — $ 148,113 Intercompany rental revenue 11,536 — (11,536) — Observatory revenue — 19,544 — 19,544 Lease termination fees 211 — — 211 Third-party management and other fees 346 — — 346 Other revenue and fees 2,010 — — 2,010 Total revenues 162,216 19,544 (11,536) 170,224 Operating expenses: Property operating expenses 41,468 — — 41,468 Intercompany rent expense — 11,536 (11,536) — Ground rent expense 2,331 — — 2,331 General and administrative expenses 15,951 — — 15,951 Observatory expenses — 8,154 — 8,154 Real estate taxes 29,254 — — 29,254 Depreciation and amortization 46,085 8 — 46,093 Total operating expenses 135,089 19,698 (11,536) 143,251 Total operating income 27,127 (154) — 26,973 Other income (expense): Interest income 637 — — 637 Interest expense (19,618) — — (19,618) Loss on early extinguishment of debt (86) — — (86) Income (loss) before income taxes 8,060 (154) — 7,906 Income tax (expense) benefit (227) 609 — 382 Net income $ 7,833 $ 455 $ — $ 8,288 Segment assets $ 4,409,281 $ 255,277 $ — $ 4,664,558 Expenditures for segment assets $ 26,570 $ 1,237 $ — $ 27,807

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events None.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Quarterly Presentation	The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”), for interim financial information, and with the rules and regulations of the Securities and Exchange Commission (the "SEC"). Accordingly, certain information and footnote disclosures required by GAAP for complete financial statements have been condensed or omitted in accordance with such rules and regulations. In the opinion of management, all adjustments and eliminations (including intercompany balances and transactions), consisting of normal recurring adjustments, considered necessary for the fair presentation of the financial statements have been included.
Principles of Consolidation	The results of operations for the periods presented are not necessarily indicative of the results that may be expected for the corresponding full years. These financial statements should be read in conjunction with the financial statements and accompanying notes included in the financial statements for the year ended December 31, 2020 contained in our Annual Report on Form 10-K. We do not consider our business to be subject to material seasonal fluctuations, except that our observatory business is subject to tourism seasonality and currently impacted by the Coronavirus 19 ("COVID-19") pandemic.
Principles of Consolidation for Variable Interest Entities	We consolidate entities in which we have a controlling financial interest.  In determining whether we have a controlling financial interest in a partially owned entity and the requirement to consolidate the accounts of that entity, we consider factors such as ownership interest, board representation, management representation, authority to make decisions, and contractual and substantive participating rights of the partners/members.  For variable interest entities ("VIE"), we consolidate the entity if we are deemed to have a variable interest in the entity and through that interest we are deemed the primary beneficiary. The primary beneficiary of a VIE 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. The primary beneficiary is required to consolidate the VIE. The Operating Partnership is a variable interest entity of our company, Empire State Realty Trust, Inc.  As the Operating Partnership is already consolidated in the financial statements of Empire State Realty Trust, Inc., the identification of this entity as a variable interest entity has no impact on our consolidated financial statements.    We will assess the accounting treatment for each investment we may have in the future. This assessment will include a review of each entity’s organizational agreement to determine which party has what rights and whether those rights are protective or participating. For all VIEs, we will review such agreements in order to determine which party has the power to direct the activities that most significantly impact the entity’s economic performance and benefit. In situations where we or our partner could approve, among other things, the annual budget, or leases that cover more than a nominal amount of space relative to the total rentable space at each property, we would not consolidate the investment as we consider these to be substantive participation rights that result in shared power of the activities that would most significantly impact the performance and benefit of such joint venture investment.     A non-controlling interest in a consolidated subsidiary is defined as the portion of the equity (net assets) in a subsidiary not attributable, directly or indirectly, to a parent. Non-controlling interests are required to be presented as a separate component of equity in the condensed consolidated balance sheets and in the condensed consolidated statements of operations by requiring earnings and other comprehensive income to be attributed to controlling and non-controlling interests.
Accounting Estimates	The preparation of the condensed consolidated financial statements in accordance with GAAP requires management to use estimates and assumptions that in certain circumstances affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities, and the reported revenues and expenses. Significant items subject to such estimates and assumptions include allocation of the purchase price of acquired real estate properties among tangible and intangible assets, determination of the useful life of real estate properties and other long-lived assets, valuation and impairment analysis of commercial real estate properties, right of use assets and other long-lived and indefinite lived assets, estimate of tenant expense reimbursements, valuation of the allowance for doubtful accounts, and valuation of derivative instruments, ground lease liabilities, senior unsecured notes, mortgage notes payable, unsecured term loan and revolving credit facilities, and equity based compensation. These estimates are prepared using management’s best judgment, after considering past, current, and expected events and economic conditions. Actual results could differ from those estimates.
Recently Issued or Adopted Accounting Standards	During April 2020, the Financial Accounting Standards Board ("FASB") staff issued a question and answer document (the “Lease Modification Q&A”) focused on the application of lease accounting guidance to lease concessions provided as a result of the COVID-19 pandemic. Under existing lease guidance, the entity would have to determine, on a lease by lease basis, if a lease concession was the result of a new arrangement reached with the tenant, which would be accounted for under the lease modification framework, or if a lease concession was under the enforceable rights and obligations that existed in the original lease, which would be accounted for outside the lease modification framework. The Lease Modification Q&A provides entities with the option to elect to account for lease concessions as though the enforceable rights and obligations existed in the original lease. This election is only available when total cash flows resulting from the modified lease are substantially similar to the cash flows in the original lease.     During March 2020, the FASB issued Accounting Standards Update ("ASU") 2020-04, Reference Rate Reform (Topic 848). ASU 2020-04 contains practical expedients for reference rate reform related activities that impact debt, leases, derivatives and other contracts. The guidance in ASU 2020-04 is optional and may be elected over time as reference rate reform activities occur. During the first quarter 2020, we elected to apply the hedge accounting expedients related to probability and the assessments of effectiveness for future LIBOR-indexed cash flows to assume that the index upon which future hedged transactions will be based matches the index on the corresponding derivatives. Application of these expedients preserves the presentation of derivatives consistent with past presentation. We continue to evaluate the impact of the guidance and may apply other elections as applicable as additional changes in the market occur.
Fair Valuation	The estimated fair values at March 31, 2021 and December 31, 2020 were determined by management, using available market information and appropriate valuation methodologies. Considerable judgment is necessary to interpret market data and develop estimated fair value. Accordingly, the estimates presented herein are not necessarily indicative of the amounts we could realize on disposition of the financial instruments. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts.     The fair value of derivative instruments is determined using widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. Although the majority of the inputs used to value our derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with our derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by ourselves and our counterparties. The impact of such credit valuation adjustments, determined based on the fair value of each individual contract, was not significant to the overall valuation. As a result, all of our derivatives were classified as Level 2 of the fair value hierarchy.    The fair value of our mortgage notes payable, senior unsecured notes - Series A, B, C, D, E, F, G and H, unsecured term loan facilities, unsecured revolving credit facility and ground lease liabilities which are determined using Level 3 inputs, are estimated by discounting the future cash flows using current interest rates at which similar borrowings could be made to us.

Deferred Costs, Acquired Leas_2

Deferred Costs, Acquired Lease Intangibles and Goodwill (Tables)	3 Months Ended
	Mar. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred costs, net	Deferred costs, net, consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Leasing costs $ 203,730 $ 203,905 Acquired in-place lease value and deferred leasing costs 180,131 181,336 Acquired above-market leases 40,254 40,398 424,115 425,639 Less: accumulated amortization (225,967) (223,918) Total deferred costs, net, excluding net deferred financing costs $ 198,148 $ 201,721 March 31, 2021 December 31, 2020 Financing costs $ 42,689 $ 35,365 Less: accumulated amortization (19,202) (17,998) Total deferred financing costs, net $ 23,487 $ 17,367
Amortizing acquired intangible assets and liabilities	Amortizing acquired intangible assets and liabilities consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Acquired below-market ground leases $ 396,916 $ 396,916 Less: accumulated amortization (54,139) (52,181) Acquired below-market ground leases, net $ 342,777 $ 344,735 March 31, 2021 December 31, 2020 Acquired below-market leases $ (77,686) $ (78,451) Less: accumulated amortization 47,574 46,746 Acquired below-market leases, net $ (30,112) $ (31,705)

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Long-term debt	Debt consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): Principal Balance As of March 31, 2021 March 31, 2021 December 31, 2020 Stated Effective (1) Maturity (2) Mortgage debt collateralized by: Fixed rate mortgage debt Metro Center $ 86,803 $ 87,382 3.59 % 3.68 % 11/5/2024 10 Union Square 50,000 50,000 3.70 % 3.97 % 4/1/2026 1542 Third Avenue 30,000 30,000 4.29 % 4.53 % 5/1/2027 First Stamford Place (3) 180,000 180,000 4.28 % 4.71 % 7/1/2027 1010 Third Avenue and 77 West 55th Street 37,278 37,477 4.01 % 4.23 % 1/5/2028 250 West 57th Street 180,000 180,000 2.83 % 3.19 % 12/1/2030 10 Bank Street 31,795 32,025 4.23 % 4.36 % 6/1/2032 383 Main Avenue 30,000 30,000 4.44 % 4.55 % 6/30/2032 1333 Broadway 160,000 160,000 4.21 % 4.29 % 2/5/2033 Total mortgage debt 785,876 786,884 Senior unsecured notes: (4) Series A 100,000 100,000 3.93 % 3.96 % 3/27/2025 Series B 125,000 125,000 4.09 % 4.12 % 3/27/2027 Series C 125,000 125,000 4.18 % 4.21 % 3/27/2030 Series D 115,000 115,000 4.08 % 4.11 % 1/22/2028 Series E 160,000 160,000 4.26 % 4.27 % 3/22/2030 Series F 175,000 175,000 4.44 % 4.45 % 3/22/2033 Series G 100,000 100,000 3.61 % 4.89 % 3/17/2032 Series H 75,000 75,000 3.73 % 5.00 % 3/17/2035 Unsecured term loan facility (4) 215,000 215,000 LIBOR plus 1.20% 3.56 % 3/19/2025 Unsecured revolving credit facility (4) — — LIBOR plus 1.30% — 3/31/2025 Unsecured term loan facility (4) 175,000 175,000 LIBOR plus 1.50% 3.60 % 12/31/2026 Total principal 2,150,876 2,151,884 Deferred financing costs, net (14,575) (15,235) Total $ 2,136,301 $ 2,136,649 ______________ (1) The effective rate is the yield as of March 31, 2021 and includes the stated interest rate, deferred financing cost amortization and interest associated with variable to fixed interest rate swap agreements. (2) Pre-payment is generally allowed for each loan upon payment of a customary pre-payment penalty. (3) Represents a $164 million mortgage loan bearing interest at 4.09% and a $16 million loan bearing interest at 6.25%. (4) At March 31, 2021, we were in compliance with all debt covenants.
Aggregate required principal payments	Aggregate required principal payments at March 31, 2021 are as follows (amounts in thousands): Year Amortization Maturities Total 2021 $ 3,082 $ — $ 3,082 2022 5,628 — 5,628 2023 7,876 — 7,876 2024 7,958 77,675 85,633 2025 5,826 315,000 320,826 Thereafter 20,084 1,707,747 1,727,831 Total $ 50,454 $ 2,100,422 $ 2,150,876
Deferred financing costs, net	Deferred costs, net, consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Leasing costs $ 203,730 $ 203,905 Acquired in-place lease value and deferred leasing costs 180,131 181,336 Acquired above-market leases 40,254 40,398 424,115 425,639 Less: accumulated amortization (225,967) (223,918) Total deferred costs, net, excluding net deferred financing costs $ 198,148 $ 201,721 March 31, 2021 December 31, 2020 Financing costs $ 42,689 $ 35,365 Less: accumulated amortization (19,202) (17,998) Total deferred financing costs, net $ 23,487 $ 17,367

Accounts Payable and Accrued _2

Accounts Payable and Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2021
Payables and Accruals [Abstract]
Accounts payable and accrued expenses	Accounts payable and accrued expenses consisted of the following as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 December 31, 2020 Accrued capital expenditures $ 60,536 $ 58,057 Accounts payable and accrued expenses 30,032 32,309 Interest rate swap agreements liability 7,450 8,849 Accrued interest payable 3,436 3,219 Due to affiliated companies 927 769 Total accounts payable and accrued expenses $ 102,381 $ 103,203

Financial Instruments and Fai_2

Financial Instruments and Fair Values (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Summary of the terms of the agreement and the fair value of derivative financial instruments	The table below summarizes the terms of agreements and the fair values of our derivative financial instruments as of March 31, 2021 and December 31, 2020 (dollar amounts in thousands): March 31, 2021 December 31, 2020 Derivative Notional Amount Receive Rate Pay Rate Effective Date Expiration Date Asset Liability Asset Liability Interest rate swap $ 265,000 1 Month LIBOR 2.1485% August 31, 2017 August 24, 2022 $ — $ (7,450) $ — $ (8,849)
Effect of our derivative financial instruments designated as cash flow hedges on accumulated other comprehensive income (loss)	The table below shows the effect of our derivative financial instruments designated as cash flow hedges on accumulated other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 (amounts in thousands): Three Months Ended Effects of Cash Flow Hedges March 31, 2021 March 31, 2020 Amount of gain (loss) recognized in other comprehensive income (loss) $ 59 $ (17,695) Amount of gain (loss) reclassified from accumulated other comprehensive (loss) into interest expense (2,869) (796) The table below shows the effect of our derivative financial instruments designated as cash flow hedges on the condensed consolidated statements of operations for the three months ended March 31, 2021 and 2020 (amounts in thousands): Three Months Ended Effects of Cash Flow Hedges March 31, 2021 March 31, 2020 Total interest (expense) presented in the condensed consolidated statements of operations in which the effects of cash flow hedges are recorded $ (23,554) $ (19,618) Amount of gain (loss) reclassified from accumulated other comprehensive (loss) into interest expense (2,869) (796)
Summary of the carrying and estimated fair values of financial instruments	The following tables summarize the carrying and estimated fair values of our financial instruments as of March 31, 2021 and December 31, 2020 (amounts in thousands): March 31, 2021 Estimated Fair Value Carrying Total Level 1 Level 2 Level 3 Interest rate swap included in accounts payable and accrued expenses $ 7,450 $ 7,450 $ — $ 7,450 $ — Mortgage notes payable 775,276 772,147 — — 772,147 Senior unsecured notes - Series A, B, C, D, E, F, G and H 973,214 986,839 — — 986,839 Unsecured term loan facilities 387,811 390,000 — — 390,000 December 31, 2020 Estimated Fair Value Carrying Total Level 1 Level 2 Level 3 Interest rate swap included in accounts payable and accrued expenses $ 8,849 $ 8,849 $ — $ 8,849 $ — Mortgage notes payable 775,929 808,294 — — 808,294 Senior unsecured notes - Series A, B, C, D, E, F, G and H 973,159 1,039,857 — — 1,039,857 Unsecured term loan facilities 387,561 390,000 — — 390,000

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Components of rental revenue	The components of rental revenue for the three months ended March 31, 2021 and 2020 are as follows (amounts in thousands): Three Months Ended Rental revenue March 31, 2021 March 31, 2020 Fixed payments $ 125,773 $ 130,514 Variable payments 14,458 17,599 Total rental revenue $ 140,231 $ 148,113
Future contractual minimum lease payments on non-cancellable operating leases to be received (current year-to-date)	As of March 31, 2021, we were entitled to the following future contractual minimum lease payments (excluding operating expense reimbursements) on non-cancellable operating leases to be received which expire on various dates through 2038 (amounts in thousands): Remainder of 2021 $ 369,719 2022 490,994 2023 471,638 2024 435,036 2025 396,144 Thereafter 1,859,648 $ 4,023,179
Future minimum lease payments to be paid	As of March 31, 2021, the following table summarizes our future minimum lease payments discounted by our incremental borrowing rates to calculate the lease liabilities of our leases (amounts in thousands): Remainder of 2021 $ 1,139 2022 1,518 2023 1,518 2024 1,518 2025 1,518 Thereafter 65,262 Total undiscounted cash flows 72,473 Present value discount (43,422) Ground lease liabilities $ 29,051

Equity (Tables)

Equity (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Net income attributable to common stockholders and the issuance of our Class A shares in exchange for the conversion of OP Units into common stock	The following is net income attributable to common stockholders and the issuance of our Class A shares in exchange for the conversion of OP Units into common stock (amounts in thousands): Three Months Ended March 31, 2021 March 31, 2020 Net income (loss) attributable to common stockholders $ (2,621) $ 4,495 Increase in additional paid-in capital for the conversion of OP Units into common stock 2,689 7,661 Change from net income (loss) attributable to common stockholders and transfers from non-controlling interests $ 68 $ 12,156
Schedule of Equity Securities Repurchased	The following table summarizes our purchases of equity securities each of the three months ended March 31, 2021: Period Total Number of Shares Purchased Weighted Average Price Paid per Share Total Number of Shares Purchased as Part of Publicly Announced Plan Maximum Approximate Dollar Value Available for Future Purchase (in thousands) January 2021 337,339 $ 9.17 337,339 $ 496,908 February 2021 45,732 $ 9.65 45,732 $ 496,467 March 2021 — $ — — $ 496,467
Summary of restricted stock and LTIP unit activity	The following is a summary of restricted stock and LTIP unit activity for the three months ended March 31, 2021: Restricted Stock LTIP Units Weighted Average Grant Fair Value Unvested balance at December 31, 2020 217,700 7,750,284 $ 6.94 Vested (70,338) (847,406) 11.94 Granted 120,895 2,059,840 8.38 Forfeited or unearned (9,495) (1,417,107) 5.47 Unvested balance at March 31, 2021 258,762 7,545,611 $ 7.02
Earnings per share	Earnings per share for the three months ended March 31, 2021 and 2020 is computed as follows (amounts in thousands, except per share amounts): Three Months Ended March 31, 2021 March 31, 2020 Numerator - Basic: Net income (loss) $ (3,191) $ 8,288 Private perpetual preferred unit distributions (1,050) (1,050) Net income (loss) attributable to non-controlling interests 1,620 (2,743) Earnings allocated to unvested shares — (11) Net income (loss) attributable to common stockholders – basic $ (2,621) $ 4,484 Numerator - Diluted: Net income (loss) $ (3,191) $ 8,288 Private perpetual preferred unit distributions (1,050) (1,050) Earnings allocated to unvested shares — (11) Net income (loss) attributable to common stockholders – diluted $ (4,241) $ 7,227 Denominator: Weighted average shares outstanding – basic 171,735 181,741 Operating partnership units 106,146 110,904 Effect of dilutive securities: Stock-based compensation plans — — Weighted average shares outstanding – diluted 277,881 292,645 Earnings (loss) per share: Basic $ (0.02) $ 0.02 Diluted $ (0.02) $ 0.02

Segment Reporting (Tables)

Segment Reporting (Tables)	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Components of segment net income (loss) for each segment	The following tables provide components of segment net income (loss) for each segment for the three and three months ended March 31, 2021 and 2020 (amounts in thousands): Three Months Ended March 31, 2021 Real Estate Observatory Intersegment Elimination Total Revenues: Rental revenue $ 140,231 $ — $ — $ 140,231 Intercompany rental revenue 4,932 — (4,932) — Observatory revenue — 2,603 — 2,603 Lease termination fees 1,289 — — 1,289 Third-party management and other fees 276 — — 276 Other revenue and fees 905 — — 905 Total revenues 147,633 2,603 (4,932) 145,304 Operating expenses: Property operating expenses 30,279 — — 30,279 Intercompany rent expense — 4,932 (4,932) — Ground rent expense 2,331 — — 2,331 General and administrative expenses 13,853 — — 13,853 Observatory expenses — 4,588 — 4,588 Real estate taxes 31,447 — — 31,447 Depreciation and amortization 44,419 38 — 44,457 Total operating expenses 122,329 9,558 (4,932) 126,955 Total operating income (loss) 25,304 (6,955) — 18,349 Other income (expense): Interest income 120 2 — 122 Interest expense (23,554) — — (23,554) Loss on early extinguishment of debt (214) — — (214) Income (loss) before income taxes 1,656 (6,953) — (5,297) Income tax (expense) benefit (283) 2,389 — 2,106 Net income (loss) $ 1,373 $ (4,564) $ — $ (3,191) Segment assets $ 3,910,152 $ 241,371 $ — $ 4,151,523 Expenditures for segment assets $ 23,331 $ 4 $ — $ 23,335 Three Months Ended March 31, 2020 Real Estate Observatory Intersegment Elimination Total Revenues: Rental revenue $ 148,113 $ — $ — $ 148,113 Intercompany rental revenue 11,536 — (11,536) — Observatory revenue — 19,544 — 19,544 Lease termination fees 211 — — 211 Third-party management and other fees 346 — — 346 Other revenue and fees 2,010 — — 2,010 Total revenues 162,216 19,544 (11,536) 170,224 Operating expenses: Property operating expenses 41,468 — — 41,468 Intercompany rent expense — 11,536 (11,536) — Ground rent expense 2,331 — — 2,331 General and administrative expenses 15,951 — — 15,951 Observatory expenses — 8,154 — 8,154 Real estate taxes 29,254 — — 29,254 Depreciation and amortization 46,085 8 — 46,093 Total operating expenses 135,089 19,698 (11,536) 143,251 Total operating income 27,127 (154) — 26,973 Other income (expense): Interest income 637 — — 637 Interest expense (19,618) — — (19,618) Loss on early extinguishment of debt (86) — — (86) Income (loss) before income taxes 8,060 (154) — 7,906 Income tax (expense) benefit (227) 609 — 382 Net income $ 7,833 $ 455 $ — $ 8,288 Segment assets $ 4,409,281 $ 255,277 $ — $ 4,664,558 Expenditures for segment assets $ 26,570 $ 1,237 $ — $ 27,807

Description of Business and O_2

Description of Business and Organization (Details) ft² in Millions	3 Months Ended
	Mar. 31, 2021ft²office_and_propertyparcel
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	10.1
Office Building
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	9.4
Number of properties | office_and_property	14
Office Building | Manhattan
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	7.6
Number of properties | office_and_property	9
Office Building | Fairfield County, Connecticut and Westchester County, New York
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	1.8
Number of properties | office_and_property	5
Long-term ground leasehold interests
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of properties | parcel	3
Retail Site | Manhattan and Westport, Connecticut
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	0.2
Retail Site | Manhattan
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	0.5
Number of properties | office_and_property	4
Retail Site | Westport, Connecticut
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of properties | office_and_property	2
Other Property | Stamford, Connecticut
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Area of real estate property (in square feet)	0.4
Empire State Realty Trust | Empire State Realty OP
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
OP units owned by the Company (as a percent)	60.30%

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	Mar. 31, 2021
Minimum
Accounting Policies [Line Items]
Observatory revenue realized during the first quarter, previous ten years (as a percent)	16.00%
Observatory revenue realized during the second quarter, previous ten years (as a percent)	26.00%
Observatory revenue realized during the third quarter, previous ten years (as a percent)	31.00%
Observatory revenue realized during the fourth quarter, previous ten years (as a percent)	23.00%
Maximum
Accounting Policies [Line Items]
Observatory revenue realized during the first quarter, previous ten years (as a percent)	18.00%
Observatory revenue realized during the second quarter, previous ten years (as a percent)	28.00%
Observatory revenue realized during the third quarter, previous ten years (as a percent)	33.00%
Observatory revenue realized during the fourth quarter, previous ten years (as a percent)	25.00%

Deferred Costs, Acquired Leas_3

Deferred Costs, Acquired Lease Intangibles and Goodwill - Deferred Costs, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Leasing costs	$ 203,730	$ 203,905
Total deferred costs, gross amount	424,115	425,639
Less: accumulated amortization	(225,967)	(223,918)
Total deferred costs, net, excluding net deferred financing costs	198,148	201,721
Acquired in-place lease value and deferred leasing costs
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets	180,131	181,336
Acquired above-market leases
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets	$ 40,254	$ 40,398

Deferred Costs, Acquired Leas_4

Deferred Costs, Acquired Lease Intangibles and Goodwill - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Jun. 30, 2020
Deferred Costs [Line Items]
Amortization expense related to deferred leasing costs and acquired deferred leasing costs	$ 5,600	$ 5,900
Rental revenue related to the amortization of below-market leases, net of above-market leases	654	908
Goodwill	491,479		$ 491,479
Observatory
Deferred Costs [Line Items]
Fair value in excess of carrying value (less than) (as a percent)				10.00%
Observatory
Deferred Costs [Line Items]
Goodwill	227,500
Real estate
Deferred Costs [Line Items]
Goodwill	264,000
Lease agreements
Deferred Costs [Line Items]
Amortization expense related to acquired lease intangibles	1,700	$ 2,000
Unsecured revolving credit facility | Revolving credit facility
Deferred Costs [Line Items]
Net deferred financing costs	$ 8,900		$ 2,100

Deferred Costs, Acquired Leas_5

Deferred Costs, Acquired Lease Intangibles and Goodwill - Amortizing Acquired Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Acquired below-market ground leases, net
Acquired below-market ground leases	$ 396,916	$ 396,916
Less: accumulated amortization	(54,139)	(52,181)
Acquired below-market ground leases, net	342,777	344,735
Acquired below-market leases, net
Acquired below-market leases	(77,686)	(78,451)
Less: accumulated amortization	47,574	46,746
Acquired below-market leases, net	$ (30,112)	$ (31,705)

Debt - Long-Term Debt (Details)

Debt - Long-Term Debt (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Mar. 17, 2020
Debt Instrument [Line Items]
Unsecured revolving credit facility	$ 0	$ 0
Total principal	2,150,876,000
Deferred financing costs, net	(23,487,000)	(17,367,000)
Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	785,876,000	786,884,000
Mortgages, senior notes, and unsecured term loan facilities, not including unsecured revolving credit facility
Debt Instrument [Line Items]
Total principal	2,150,876,000	2,151,884,000
Deferred financing costs, net	(14,575,000)	(15,235,000)
Total	2,136,301,000	2,136,649,000
Metro Center | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 86,803,000	87,382,000
Stated Rate (as a percent)	3.59%
Effective Rate (as a percent)	3.68%
10 Union Square | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 50,000,000	50,000,000
Stated Rate (as a percent)	3.70%
Effective Rate (as a percent)	3.97%
1542 Third Avenue | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 30,000,000	30,000,000
Stated Rate (as a percent)	4.29%
Effective Rate (as a percent)	4.53%
First Stamford Place | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 180,000,000	180,000,000
Stated Rate (as a percent)	4.28%
Effective Rate (as a percent)	4.71%
First Stamford Place - First Lien | Fixed rate mortgage debt
Debt Instrument [Line Items]
Stated Rate (as a percent)	4.09%
Face amount	$ 164,000,000
First Stamford Place - Second Lien | Fixed rate mortgage debt
Debt Instrument [Line Items]
Stated Rate (as a percent)	6.25%
Face amount	$ 16,000,000
1010 Third Avenue and 77 West 55th Street | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 37,278,000	37,477,000
Stated Rate (as a percent)	4.01%
Effective Rate (as a percent)	4.23%
250 West 57th Street | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 180,000,000	180,000,000
Stated Rate (as a percent)	2.83%
Effective Rate (as a percent)	3.19%
10 Bank Street | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 31,795,000	32,025,000
Stated Rate (as a percent)	4.23%
Effective Rate (as a percent)	4.36%
383 Main Avenue | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 30,000,000	30,000,000
Stated Rate (as a percent)	4.44%
Effective Rate (as a percent)	4.55%
1333 Broadway | Fixed rate mortgage debt
Debt Instrument [Line Items]
Fixed rate mortgage debt	$ 160,000,000	160,000,000
Stated Rate (as a percent)	4.21%
Effective Rate (as a percent)	4.29%
Senior unsecured notes, Series A | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 100,000,000	100,000,000
Stated Rate (as a percent)	3.93%
Effective Rate (as a percent)	3.96%
Senior unsecured notes, Series B | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 125,000,000	125,000,000
Stated Rate (as a percent)	4.09%
Effective Rate (as a percent)	4.12%
Senior unsecured notes, Series C | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 125,000,000	125,000,000
Stated Rate (as a percent)	4.18%
Effective Rate (as a percent)	4.21%
Senior unsecured notes, Series D | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 115,000,000	115,000,000
Stated Rate (as a percent)	4.08%
Effective Rate (as a percent)	4.11%
Senior unsecured notes, Series E | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 160,000,000	160,000,000
Stated Rate (as a percent)	4.26%
Effective Rate (as a percent)	4.27%
Senior unsecured notes, Series F | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 175,000,000	175,000,000
Stated Rate (as a percent)	4.44%
Effective Rate (as a percent)	4.45%
Senior unsecured notes, Series G | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 100,000,000	100,000,000
Stated Rate (as a percent)	3.61%		3.61%
Effective Rate (as a percent)	4.89%
Face amount			$ 100,000,000
Senior unsecured notes, Series H | Senior unsecured notes
Debt Instrument [Line Items]
Total	$ 75,000,000	75,000,000
Stated Rate (as a percent)	3.73%		3.73%
Effective Rate (as a percent)	5.00%
Face amount			$ 75,000,000
Unsecured term loan facilities | Revolving credit facility
Debt Instrument [Line Items]
Unsecured revolving credit facility	$ 215,000,000	215,000,000
Effective Rate (as a percent)	3.56%
Unsecured term loan facilities | Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.20%
Unsecured revolving credit facility | Revolving credit facility
Debt Instrument [Line Items]
Unsecured revolving credit facility	$ 0	0
Effective Rate (as a percent)	0.00%
Unsecured revolving credit facility | Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.30%
Unsecured term loan facility | Revolving credit facility
Debt Instrument [Line Items]
Unsecured revolving credit facility	$ 175,000,000	$ 175,000,000
Effective Rate (as a percent)	3.60%
Unsecured term loan facility | Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.50%

Debt - Aggregate Required Princ

Debt - Aggregate Required Principal Payments (Details) $ in Thousands	Mar. 31, 2021USD ($)
Amortization
2021	$ 3,082
2022	5,628
2023	7,876
2024	7,958
2025	5,826
Thereafter	20,084
Total	50,454
Maturities
2021	0
2022	0
2023	0
2024	77,675
2025	315,000
Thereafter	1,707,747
Total	2,100,422
Total
2021	3,082
2022	5,628
2023	7,876
2024	85,633
2025	320,826
Thereafter	1,727,831
Total	$ 2,150,876

Debt - Deferred Financing Costs

Debt - Deferred Financing Costs, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Debt Disclosure [Abstract]
Financing costs	$ 42,689		$ 35,365
Less: accumulated amortization	(19,202)		(17,998)
Total deferred financing costs, net	23,487		$ 17,367
Amortization related to deferred financing costs	$ 1,200	$ 900

Debt - Unsecured Revolving Cred

Debt - Unsecured Revolving Credit and Term Loan Facilities (Details)	Mar. 31, 2021USD ($)option	Dec. 31, 2021	Dec. 31, 2020USD ($)
Line of Credit Facility [Line Items]
Outstanding borrowings	$ 0		$ 0
Unsecured revolving credit facility and term loan | Revolving credit facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	1,065,000,000
Unsecured revolving credit facility higher borrowing capacity option	1,500,000,000
Unsecured revolving credit facility | Revolving credit facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	850,000,000
Outstanding borrowings	$ 0		0
Number of options to extend maturity | option	2
Extension period (in months)	6 months
Term loan facility | Revolving credit facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 215,000,000
Outstanding borrowings	215,000,000		215,000,000
Unsecured term loan facility | Revolving credit facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	175,000,000
Unsecured revolving credit facility higher borrowing capacity option	225,000,000
Outstanding borrowings	$ 175,000,000		$ 175,000,000
Minimum | Unsecured revolving credit facility | Revolving credit facility
Line of Credit Facility [Line Items]
Extension fee, as a percent of outstanding commitments under revolving credit facility	0.0625%
Maximum | Unsecured revolving credit facility | Revolving credit facility
Line of Credit Facility [Line Items]
Extension fee, as a percent of outstanding commitments under revolving credit facility	0.075%
Forecast | Unsecured term loan facility | Revolving credit facility
Line of Credit Facility [Line Items]
Prepayment fee, as a percent of principal amount prepaid		1.00%

Debt - Senior Unsecured Notes (

Debt - Senior Unsecured Notes (Details) - Senior notes - USD ($)	Mar. 17, 2020	Mar. 31, 2021
Series G and Series H Senior Unsecured Notes
Debt Instrument [Line Items]
Face amount	$ 175,000,000
Issue price, as a percent of aggregate principal amount	100.00%
Senior unsecured notes, Series G
Debt Instrument [Line Items]
Face amount	$ 100,000,000
Stated rate (as a percent)	3.61%	3.61%
Senior unsecured notes, Series H
Debt Instrument [Line Items]
Face amount	$ 75,000,000
Stated rate (as a percent)	3.73%	3.73%

Accounts Payable and Accrued _3

Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued capital expenditures	$ 60,536	$ 58,057
Accounts payable and accrued expenses	30,032	32,309
Interest rate swap agreements liability	7,450	8,849
Accrued interest payable	3,436	3,219
Due to affiliated companies	927	769
Total accounts payable and accrued expenses	$ 102,381	$ 103,203

Financial Instruments and Fai_3

Financial Instruments and Fair Values - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements liability	$ 7,450,000		$ 8,849,000
Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements liability	7,500,000
Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional value	265,000,000		265,000,000
Net unrealized gain (loss)	2,900,000	$ (16,900,000)
Net loss to be reclassified into interest expense within the next 12 months	(11,500,000)
Accounts payable and accrued expenses | Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements liability	$ 7,500,000		$ 8,800,000

Financial Instruments and Fai_4

Financial Instruments and Fair Values - Summary of the Terms of Agreements and the Fair Value of Derivative Financial Instruments (Details) - Designated as Hedging Instrument - Cash Flow Hedging - LIBOR - Interest Rate Swap, One Month LIBOR, 2.1485% - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Notional Amount	$ 265,000,000
Pay Rate	2.1485%
Asset	$ 0	$ 0
Liability	$ (7,450,000)	$ (8,849,000)

Financial Instruments and Fai_5

Financial Instruments and Fair Values - Effect of Derivative Financial Instruments Designated as Cash Flow Hedges (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (loss)	$ 59	$ (17,695)
Amount of gain (loss) reclassified from accumulated other comprehensive (loss) into interest expense	(2,869)	(796)
Interest expense	(23,554)	(19,618)
Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (loss)	59	(17,695)
Amount of gain (loss) reclassified from accumulated other comprehensive (loss) into interest expense	(2,869)	(796)
Reclassification out of Accumulated Other Comprehensive Income | Accumulated other comprehensive income (loss) | Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	$ (2,869)	$ (796)

Financial Instruments and Fai_6

Financial Instruments and Fair Values - Summary of the Carrying and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	$ 7,450	$ 8,849
Carrying Value | Mortgage notes payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	775,276	775,929
Carrying Value | Senior notes | Senior unsecured notes - Series A, B, C, D, E, F, G and H
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	973,214	973,159
Estimated Fair Value | Mortgage notes payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	772,147	808,294
Estimated Fair Value | Senior notes | Senior unsecured notes - Series A, B, C, D, E, F, G and H
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	986,839	1,039,857
Level 1 | Estimated Fair Value | Mortgage notes payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Level 1 | Estimated Fair Value | Senior notes | Senior unsecured notes - Series A, B, C, D, E, F, G and H
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Level 2 | Estimated Fair Value | Mortgage notes payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Level 2 | Estimated Fair Value | Senior notes | Senior unsecured notes - Series A, B, C, D, E, F, G and H
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Level 3 | Estimated Fair Value | Mortgage notes payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	772,147	808,294
Level 3 | Estimated Fair Value | Senior notes | Senior unsecured notes - Series A, B, C, D, E, F, G and H
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	986,839	1,039,857
Revolving credit facility | Carrying Value | Unsecured term loan facilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	387,811	387,561
Revolving credit facility | Estimated Fair Value | Unsecured term loan facilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	390,000	390,000
Revolving credit facility | Level 1 | Estimated Fair Value | Unsecured term loan facilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Revolving credit facility | Level 2 | Estimated Fair Value | Unsecured term loan facilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Revolving credit facility | Level 3 | Estimated Fair Value | Unsecured term loan facilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	390,000	390,000
Interest Rate Swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	7,500
Interest Rate Swap | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	7,450	8,849
Interest Rate Swap | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	7,450	8,849
Interest Rate Swap | Level 1 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	0	0
Interest Rate Swap | Level 2 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	7,450	8,849
Interest Rate Swap | Level 3 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap included in accounts payable and accrued expenses	$ 0	$ 0

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Thousands	Mar. 31, 2021USD ($)property	Dec. 31, 2020USD ($)
Operating Leases [Line Items]
Right-of-use assets	$ 29,051	$ 29,104
Lease liabilities	$ 29,051	$ 29,104
Number of properties subject to ground leases | property	3
Weighted average discount rate	4.50%
Weighted average remaining lease term (in years)	49 years 1 month 6 days
Minimum
Operating Leases [Line Items]
Term of lease (in years)	1 year
Maximum
Operating Leases [Line Items]
Term of lease (in years)	21 years

Leases - Components of Rental R

Leases - Components of Rental Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Leases [Abstract]
Fixed payments	$ 125,773	$ 130,514
Variable payments	14,458	17,599
Total rental revenue	$ 140,231	$ 148,113

Leases - Future Contractual Min

Leases - Future Contractual Minimum Lease Payments On Non-Cancellable Operating Leases To Be Received (Details) $ in Thousands	Mar. 31, 2021USD ($)
Leases [Abstract]
Remainder of 2021	$ 369,719
2022	490,994
2023	471,638
2024	435,036
2025	396,144
Thereafter	1,859,648
Total future minimum lease payments on non-cancellable operating leases to be received	$ 4,023,179

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments on Ground Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Remainder of 2021	$ 1,139
2022	1,518
2023	1,518
2024	1,518
2025	1,518
Thereafter	65,262
Total undiscounted cash flows	72,473
Present value discount	(43,422)
Ground lease liabilities	$ 29,051	$ 29,104

Commitments and Contingencies -

Commitments and Contingencies - Legal Proceedings (Details) - New York State Supreme Court, New York County $ in Millions	Aug. 26, 2020USD ($)	Oct. 31, 2014participant
Loss Contingencies [Line Items]
Number of plaintiffs opting out of settlement (participant) | participant		12
Amount awarded to claimants | $	$ 1.2
Interest period (in years)	7 years

Commitments and Contingencies_2

Commitments and Contingencies - Unfunded Capital Expenditures (Details) $ in Millions	Mar. 31, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Estimated capital expenditures to be incurred	$ 99.3

Equity - Shares and Units (Deta

Equity - Shares and Units (Details)	3 Months Ended
	Mar. 31, 2021shares	May 16, 2019shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP Unit, redemption term for cash (in years)	1 year
OP Unit, exchange ratio to common stock	1
Dividends on common stock received until performance criteria met for LTIP units (as a percent)	10.00%
Dividends on common stock received after performance criteria met for LTIP units (as a percent)	90.00%
Dividends on common stock received in periods after performance criteria met for LTIP units (as a percent)	100.00%
OP units outstanding (in shares)	285,622,197
Empire State Realty Trust
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units owned by the Company (in shares)	172,331,871
Other Partners, Certain Directors, Officers And Other Members Of Executive Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units not owned by the Company (in shares)	113,290,326
Empire State Realty OP | Empire State Realty Trust
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units owned by the Company (as a percent)	60.30%
Empire State Realty OP | Other Partners, Certain Directors, Officers And Other Members Of Executive Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units not owned by the Company (as a percent)	39.70%
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the plan (in shares)	11,000,000	11,000,000

Equity - Change in Net Income A

Equity - Change in Net Income Attributable to Common Shareholders (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity [Abstract]
Net income (loss) attributable to common stockholders	$ (2,621)	$ 4,495
Increase in additional paid-in capital for the conversion of OP Units into common stock	2,689	7,661
Change from net income (loss) attributable to common stockholders and transfers from non-controlling interests	$ 68	$ 12,156

Equity - Equity Securities Repu

Equity - Equity Securities Repurchased (Details) - USD ($)	1 Months Ended
	Mar. 31, 2021	Feb. 28, 2021	Jan. 31, 2021
Equity [Abstract]
Stock repurchase authorized amount	$ 500,000,000
Total Number of Shares Purchased (in shares)	0	45,732	337,339
Weighted Average Price Paid per Share (in USD per share)	$ 0	$ 9.65	$ 9.17
Maximum Approximate Dollar Value Available for Future Purchase	$ 496,467,000	$ 496,467,000	$ 496,908,000

Equity - Private Perpetual Pref

Equity - Private Perpetual Preferred Units (Details) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Preferred Units [Line Items]
Dividends per share (in USD per share)	$ 0	$ 0.105
Private Perpetual Preferred Units, Series 2019
Preferred Units [Line Items]
Private perpetual preferred units, issued (in shares)	4,664,038		4,664,038
Private perpetual preferred units, per unit liquidation preference (in USD per share)	$ 13.52		$ 13.52
Cumulative preferential annual cash distributions (in USD per share)	$ 0.70
Private Perpetual Preferred Units, Series 2014
Preferred Units [Line Items]
Private perpetual preferred units, issued (in shares)	1,560,360		1,560,360
Private perpetual preferred units issued during period (in shares)	1,560,360
Private perpetual preferred units, per unit liquidation preference (in USD per share)	$ 16.62		$ 16.62
Dividends per share (in USD per share)	$ 0.60

Equity - Dividends and Distribu

Equity - Dividends and Distributions (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity [Abstract]
Dividends paid to common shareholders	$ 0	$ 18,987
Distributions paid to OP unitholders	0	12,600
Private perpetual preferred unit distributions	$ 1,050	$ 1,050

Equity - Incentive and Share-Ba

Equity - Incentive and Share-Based Compensation (Details) $ / shares in Units, $ in Millions	1 Months Ended				3 Months Ended			5 Months Ended
	Mar. 31, 2021USD ($)vesting_installmentshares	Jun. 30, 2020USD ($)shares	May 31, 2020USD ($)vesting_installmentshares	Mar. 31, 2020USD ($)vesting_installmentshares	Mar. 31, 2021USD ($)$ / sharesshares	Jun. 30, 2020	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)shares	May 16, 2019shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Retirement age (in years)					65 years	65 years	60 years
Expected volatility rate look-back period (in years)					6 years
Weighted-average per unit or share fair value (in USD per share) | $ / shares					$ 8.38
Period of service, upon completion of which, grantee's LTIP unit and restricted stock awards will immediately vest (in years)					10 years
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the plan (in shares)	11,000,000				11,000,000				11,000,000
Number of shares that remain available for future issuance (in shares)	7,800,000				7,800,000
Long-Term Incentive Plan Unit and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of share-based awards granted in period | $					$ 18.3
Weighted-average per unit or share fair value (in USD per share) | $ / shares					$ 8.38
Dividend rate (as a percent)					2.60%
Risk-free interest rate, minimum (as a percent)					0.12%
Risk free interest rate, maximum (as a percent)					0.32%
Expected price volatility, minimum (as a percent)					36.00%
Expected price volatility, maximum (as a percent)					53.00%
Time Based Long-Term Incentive Plan Unit and Time Restricted Shares | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of share-based awards granted in period | $	$ 1.5
Award vesting period (in years)	5 years
Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold of continuous service for retirement eligibility (in years)					10 years
Time Based Long-Term Incentive Plan Unit | March 2021 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	128,419
Fair value of share-based awards granted in period | $	$ 2.7
Award vesting period (in years)	4 years
Number of vesting installments | vesting_installment	3
Time Restricted Shares | March 2021 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	113,333
Market Based Long-Term Incentive Plan Unit | March 2021 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	192,760
Fair value of share-based awards granted in period | $	$ 1.5
Award vesting period (in years)	3 years
Number of vesting installments | vesting_installment	2
Tranche one | Time Based Long-Term Incentive Plan Unit and Time Restricted Shares | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	30.00%
Tranche two | Time Based Long-Term Incentive Plan Unit and Time Restricted Shares | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	30.00%
Tranche three | Time Based Long-Term Incentive Plan Unit and Time Restricted Shares | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	40.00%
2019 Plan Units | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			63,229	113,971
Fair value of share-based awards granted in period | $			$ 0.4	$ 2.3
Award vesting period (in years)				4 years
Number of vesting installments | vesting_installment				3
2019 Plan Units | Time Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				158,806
2019 Plan Units | Market Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				502,475
Fair value of share-based awards granted in period | $				$ 2.3
Award vesting period (in years)			3 years	3 years
Number of vesting installments | vesting_installment			2	2
Awards that meet age and service requirements for vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncash share-based compensation expense recognized | $					$ 1		$ 1.6
Unrecognized compensation expense | $	$ 2.1				$ 2.1
Unrecognized compensation expense, period for recognition (in years)					2 years 8 months 12 days
Awards that do not meet age and service requirements for vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncash share-based compensation expense recognized | $					$ 3.8		$ 4.3
Unrecognized compensation expense | $	$ 38.8				$ 38.8
Unrecognized compensation expense, period for recognition (in years)					2 years 8 months 12 days
Executive Officer | Time Based Long-Term Incentive Plan Unit | March 2021 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	364,199
Fair value of share-based awards granted in period | $	$ 3.4
Executive Officer | Time Based Long-Term Incentive Plan Unit | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	46,168
Executive Officer | Time Based Long-Term Incentive Plan Unit | Awards Granted in 2017, 2018, 2019 and 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)					3 years
Vesting percentage of award face amount	125.00%				125.00%
Executive Officer | Market Based Long-Term Incentive Plan Unit | March 2021 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,007,156
Fair value of share-based awards granted in period | $	$ 6.9
Executive Officer | Tranche one | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	39,472			23,049
Executive Officer | Tranche two | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	196,257			601,331
Award vesting period (in years)	3 years			3 years
Executive Officer | Tranche three | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of vesting installments | vesting_installment	2			2
Executive Officer | 2019 Plan Units, connected with bonus program | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	235,729			624,380
Fair value of share-based awards granted in period | $	$ 2.2			$ 4.4
Vesting percentage of award face amount	120.00%				120.00%
Executive Officer | 2019 Plan Units | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			82,199	745,155
Fair value of share-based awards granted in period | $			$ 0.5	$ 5.6
Executive Officer | 2019 Plan Units | Market Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			116,927	3,358,767
Fair value of share-based awards granted in period | $			$ 0.5	$ 14
Reduction of grants (in shares)		666,933
Fair value of reduction of share-based awards granted in period | $		$ 2.8
Certain Other Employees | Time Based Long-Term Incentive Plan Unit | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	85,409
Certain Other Employees | Time Restricted Shares | March 2021 Awards Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	7,562
Certain Other Employees | 2019 Plan Units | Market Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction of grants (in shares)		99,630
Fair value of reduction of share-based awards granted in period | $		$ 0.5
Director | 2019 Plan Units | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			171,153					31,117
Fair value of share-based awards granted in period | $			$ 1.1					$ 0.2
Award vesting period (in years)			3 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Age of grantee at which LTIP unit and restricted stock awards immediately vest (in years)					60 years
Minimum | Long-Term Incentive Plan Unit and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)					2 years
Minimum | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)					3 years
Minimum | Market Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)					3 years
Minimum | 2019 Plan Units | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			3 years
Number of vesting installments | vesting_installment			2
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Age of grantee at which LTIP unit and restricted stock awards immediately vest (in years)					65 years
Maximum | Long-Term Incentive Plan Unit and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)					5 years 3 months 18 days
Maximum | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)					5 years
Maximum | Market Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)					4 years
Maximum | 2019 Plan Units | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			4 years
Number of vesting installments | vesting_installment			3
Median | Time Based Long-Term Incentive Plan Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)					4 years

Equity - Summary of Restricted

Equity - Summary of Restricted Stock and LTIP Unit Activity (Details)	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Weighted Average Grant Fair Value
Beginning balance, Unvested (in USD per share) | $ / shares	$ 6.94
Vested (in USD per share) | $ / shares	11.94
Granted (in USD per share) | $ / shares	8.38
Forfeited or unearned (in USD per share) | $ / shares	5.47
Ending balance, Unvested (in USD per share) | $ / shares	$ 7.02
Restricted Stock
Restricted Stock and LTIP Units
Beginning balance, Unvested (in shares)	217,700
Vested (in shares)	(70,338)
Granted (in shares)	120,895
Forfeited or unearned (in shares)	(9,495)
Ending balance, Unvested (in shares)	258,762
LTIP Units
Restricted Stock and LTIP Units
Beginning balance, Unvested (in shares)	7,750,284
Vested (in shares)	(847,406)
Granted (in shares)	2,059,840
Forfeited or unearned (in shares)	(1,417,107)
Ending balance, Unvested (in shares)	7,545,611

Equity - Earnings Per Share (De

Equity - Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator - Basic:
Net income (loss)	$ (3,191)	$ 8,288
Private perpetual preferred unit distributions	(1,050)	(1,050)
Net income (loss) attributable to non-controlling interests	1,620	(2,743)
Earnings allocated to unvested shares	0	(11)
Net income (loss) attributable to common stockholders – basic	(2,621)	4,484
Numerator - Diluted:
Net income (loss)	(3,191)	8,288
Private perpetual preferred unit distributions	(1,050)	(1,050)
Earnings allocated to unvested shares	0	(11)
Net income (loss) attributable to common stockholders – diluted	$ (4,241)	$ 7,227
Denominator:
Weighted average shares outstanding - basic (in shares)	171,735,000	181,741,000
Operating partnership units (in shares)	106,146,000	110,904,000
Effect of dilutive securities:
Stock-based compensation plans (in shares)	0	0
Weighted average shares outstanding - diluted (in shares)	277,881,000	292,645,000
Earnings (loss) per share:
Basic (in USD per share)	$ (0.02)	$ 0.02
Diluted (in USD per share)	$ (0.02)	$ 0.02
Antidilutive securities (in shares)	315,595	399,894

Related Party Transactions (Det

Related Party Transactions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)ft²property	Mar. 31, 2020USD ($)
Related Party Transaction [Line Items]
Area of real estate property (in square feet) | ft²	10,100,000
Affiliated entities | Supervisory fee revenue
Related Party Transaction [Line Items]
Revenue from related parties	$ 200	$ 200
Affiliated entities | Property management fee revenue
Related Party Transaction [Line Items]
Revenue from related parties	40	100
Affiliated entities | Leased space rental
Related Party Transaction [Line Items]
Revenue from related parties	$ 100	$ 100
Number of properties | property	1
Notice period for lease cancellation (in days)	90 days
Undivided interest
Related Party Transaction [Line Items]
Area of real estate property (in square feet) | ft²	5,447
Chairman emeritus and employee | Leased space rental
Related Party Transaction [Line Items]
Percentage of lease space occupied by Chairman emeritus and employee	15.00%

Segment Reporting - Narrative (

Segment Reporting - Narrative (Details)	3 Months Ended
	Mar. 31, 2021segment
Segment Reporting [Abstract]
Number of reportable segments	2

Segment Reporting - Components

Segment Reporting - Components of Segment Net Income (Loss) for Each Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Revenues:
Rental revenue	$ 140,231	$ 148,113
Intercompany rental revenue	0	0
Observatory revenue	2,603	19,544
Lease termination fees	1,289	211
Third-party management and other fees	276	346
Other revenue and fees	905	2,010
Total revenues	145,304	170,224
Operating expenses:
Property operating expenses	30,279	41,468
Intercompany rent expense	0	0
Ground rent expense	2,331	2,331
General and administrative expenses	13,853	15,951
Observatory expenses	4,588	8,154
Real estate taxes	31,447	29,254
Depreciation and amortization	44,457	46,093
Total operating expenses	126,955	143,251
Total operating income	18,349	26,973
Other income (expense):
Interest income	122	637
Interest expense	(23,554)	(19,618)
Loss on early extinguishment of debt	(214)	(86)
Income (loss) before income taxes	(5,297)	7,906
Income tax (expense) benefit	2,106	382
Net income (loss)	(3,191)	8,288
Segment assets	4,151,523	4,664,558	$ 4,150,695
Expenditures for segment assets	23,335	27,807
Intersegment Elimination
Revenues:
Intercompany rental revenue	(4,932)	(11,536)
Total revenues	(4,932)	(11,536)
Operating expenses:
Intercompany rent expense	(4,932)	(11,536)
General and administrative expenses	0	0
Depreciation and amortization	0	0
Total operating expenses	(4,932)	(11,536)
Total operating income	0	0
Other income (expense):
Interest income	0	0
Interest expense	0	0
Loss on early extinguishment of debt	0	0
Income (loss) before income taxes	0	0
Income tax (expense) benefit	0	0
Net income (loss)	0	0
Segment assets	0	0
Expenditures for segment assets	0	0
Real Estate | Operating Segments
Revenues:
Rental revenue	140,231	148,113
Intercompany rental revenue	4,932	11,536
Lease termination fees	1,289	211
Third-party management and other fees	276	346
Other revenue and fees	905	2,010
Total revenues	147,633	162,216
Operating expenses:
Property operating expenses	30,279	41,468
Ground rent expense	2,331	2,331
General and administrative expenses	13,853	15,951
Real estate taxes	31,447	29,254
Depreciation and amortization	44,419	46,085
Total operating expenses	122,329	135,089
Total operating income	25,304	27,127
Other income (expense):
Interest income	120	637
Interest expense	(23,554)	(19,618)
Loss on early extinguishment of debt	(214)	(86)
Income (loss) before income taxes	1,656	8,060
Income tax (expense) benefit	(283)	(227)
Net income (loss)	1,373	7,833
Segment assets	3,910,152	4,409,281
Expenditures for segment assets	23,331	26,570
Observatory | Operating Segments
Revenues:
Intercompany rental revenue	0	0
Observatory revenue	2,603	19,544
Total revenues	2,603	19,544
Operating expenses:
Intercompany rent expense	4,932	11,536
General and administrative expenses	0	0
Observatory expenses	4,588	8,154
Depreciation and amortization	38	8
Total operating expenses	9,558	19,698
Total operating income	(6,955)	(154)
Other income (expense):
Interest income	2	0
Interest expense	0	0
Loss on early extinguishment of debt	0	0
Income (loss) before income taxes	(6,953)	(154)
Income tax (expense) benefit	2,389	609
Net income (loss)	(4,564)	455
Segment assets	241,371	255,277
Expenditures for segment assets	$ 4	$ 1,237