Extra Space Storage (EXR) 10-Q 4 Nov 24 2024 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2024	Oct. 30, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
Document Transition Report	false
Entity File Number	001-32269
Entity Registrant Name	EXTRA SPACE STORAGE INC.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	20-1076777
Entity Address, Address Line One	2795 East Cottonwood Parkway, Suite 300
Entity Address, City or Town	Salt Lake City
Entity Address, State or Province	UT
Entity Address, Postal Zip Code	84121
City Area Code	801
Local Phone Number	365-4600
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	EXR
Security Exchange Name	NYSE
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 Common Stock, Shares Outstanding		211,983,569
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001289490
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Assets:
Real estate assets, net	$ 24,385,492	$ 24,555,873
Real estate assets - operating lease right-of-use assets	694,001	227,241
Investments in unconsolidated real estate entities	1,060,213	1,071,617
Investments in debt securities and notes receivable	1,338,619	904,769
Cash and cash equivalents	88,931	99,062
Other assets, net	495,861	597,700
Total assets	28,063,117	27,456,262
Liabilities, Noncontrolling Interests and Equity:
Secured notes payable, net	1,011,705	1,273,549
Unsecured term loans, net	2,194,894	2,650,581
Unsecured senior notes, net	7,437,231	6,410,618
Revolving lines of credit	884,000	682,000
Operating lease liabilities	706,491	236,515
Cash distributions in unconsolidated real estate ventures	74,173	71,069
Accounts payable and accrued expenses	388,757	334,518
Other liabilities	407,183	383,463
Total liabilities	13,104,434	12,042,313
Commitments and contingencies
Extra Space Storage Inc. stockholders' equity:
Preferred stock, $0.01 par value, 50,000,000 shares authorized, no shares issued or outstanding	0	0
Common stock, $0.01 par value, 500,000,000 shares authorized, 211,981,742 and 211,278,803 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively	2,120	2,113
Additional paid-in capital	14,823,018	14,750,388
Accumulated other comprehensive income	3,340	17,435
Accumulated deficit	(817,865)	(379,015)
Total Extra Space Storage Inc. stockholders' equity	14,010,613	14,390,921
Noncontrolling interest represented by Preferred Operating Partnership units, net	191,306	222,360
Noncontrolling interests in Operating Partnership, net and other noncontrolling interests	756,764	800,668
Total noncontrolling interests and equity	14,958,683	15,413,949
Total liabilities, noncontrolling interests and equity	$ 28,063,117	$ 27,456,262

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value (dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	50,000,000	50,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	500,000,000	500,000,000
Common stock, issued (in shares)	211,981,742	211,278,803
Common stock, outstanding (in shares)	211,981,742	211,278,803

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues:
Property rental	$ 710,874	$ 650,887	$ 2,096,018	$ 1,525,596
Tenant reinsurance	84,048	69,128	249,100	165,265
Management fees and other income	29,882	28,019	89,888	71,609
Total revenues	824,804	748,034	2,435,006	1,762,470
Expenses:
Property operations	209,035	185,194	610,455	416,997
Tenant reinsurance	17,510	19,130	55,646	37,701
Life Storage Merger transition costs	0	54,174	0	54,174
General and administrative	39,750	37,406	123,373	107,011
Depreciation and amortization	195,046	152,338	586,821	309,914
Total expenses	461,341	448,242	1,376,295	925,797
Loss on real estate assets held for sale	(8,961)	0	(63,620)	0
Impairment of Life Storage trade name	(51,763)	0	(51,763)	0
Income from operations	302,739	299,792	943,328	836,673
Interest expense	(142,855)	(122,899)	(412,875)	(289,370)
Non-cash interest expense related to amortization of discount on Life Storage unsecured senior notes	(11,005)	(8,228)	(32,563)	(8,228)
Interest income	34,947	22,092	89,746	62,607
Income before equity in earnings and dividend income from unconsolidated real estate entities and income tax expense	183,826	190,757	587,636	601,682
Equity in earnings and dividend income from unconsolidated real estate entities	16,246	15,043	48,508	38,602
Equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets and sale of a joint venture interest	13,730	0	13,730	0
Income tax expense	(10,857)	(6,944)	(27,443)	(17,238)
Net income	202,945	198,856	622,431	623,046
Net income allocated to Preferred Operating Partnership noncontrolling interests	(1,932)	(2,253)	(6,073)	(6,761)
Net income allocated to Operating Partnership and other noncontrolling interests	(7,803)	(8,253)	(24,164)	(29,221)
Net income attributable to common stockholders	$ 193,210	$ 188,350	$ 592,194	$ 587,064
Earnings per common share
Basic (in dollars per share)	$ 0.91	$ 0.96	$ 2.79	$ 3.78
Diluted (in dollars per share)	$ 0.91	$ 0.96	$ 2.79	$ 3.78
Weighted average number of shares
Basic (in shares)	211,698,436	195,324,444	211,522,578	155,112,071
Diluted (in shares)	220,298,870	195,328,020	220,177,692	155,116,149
Cash dividends paid per common share (in dollars per share)	$ 1.62	$ 1.62	$ 4.86	$ 4.86

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 202,945	$ 198,856	$ 622,431	$ 623,046
Other comprehensive income:
Change in fair value of interest rate swaps	(24,887)	(2,264)	(14,691)	(4,175)
Total comprehensive income	178,058	196,592	607,740	618,871
Less: comprehensive income attributable to noncontrolling interests	8,749	10,395	29,641	35,693
Comprehensive income attributable to common stockholders	$ 169,309	$ 186,197	$ 578,099	$ 583,178

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Noncontrolling Interests and Equity - USD ($) $ in Thousands	Total	Redemption of units for stock	Series A Units Redemption of units for stock	Series D Units Redemption of units for stock	Preferred Operating Partnership	Preferred Operating Partnership Redemption of units for stock	Preferred Operating Partnership Series A Units Redemption of units for stock	Preferred Operating Partnership Series D Units Redemption of units for stock	Operating Partnership	Operating Partnership Redemption of units for stock	Other	Common stock	Common stock Redemption of units for stock	Common stock Series A Units Redemption of units for stock	Common stock Series D Units Redemption of units for stock	Additional Paid-in Capital	Additional Paid-in Capital Redemption of units for stock	Additional Paid-in Capital Series A Units Redemption of units for stock	Additional Paid-in Capital Series D Units Redemption of units for stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2022	$ 4,078,274				$ 261,502				$ 556,095		$ 1,080	$ 1,339				$ 3,345,332				$ 48,798	$ (135,872)
Beginning balance (in shares) at Dec. 31, 2022												133,921,020
Increase (Decrease) in Stockholders' Equity
Redemption of noncontrolling interests		$ 0	$ (5,316)	$ 0			$ (16,339)	$ (22,064)		$ (163)				$ 8	$ 2		$ 163	$ 11,015	$ 22,062
Redemption of noncontrolling interests (in shares)													2,119	851,698	154,307
Life Storage Merger issuance of common stock and Operating Partnership units (in shares)												76,217,359
Life Storage Merger issuance of common stock and Operating Partnership units	11,602,808								249,470			$ 762				11,352,576
Noncontrolling interest in consolidated joint ventures	7,309										7,309
Net income (loss)	623,046				6,761				29,353		(132)										587,064
Other comprehensive loss	(4,175)								(289)											(3,886)
Distributions to Operating Partnership units held by noncontrolling interests	(43,003)				(6,921)				(36,082)
Dividends paid on common stock	(704,069)																				(704,069)
Issuance of common stock in connection with share based compensation (in shares)												144,640
Issuance of common stock in connection with share based compensation	19,433											$ 2				19,431
Taxes paid upon net settlement of share based compensation (in shares)												(8,074)
Taxes paid upon net settlement of share based compensation	(7,606)															(7,606)
Restricted stock grants cancelled (in shares)												(6,983)
Ending balance at Sep. 30, 2023	15,566,701				222,939				798,384		8,257	$ 2,113				14,742,973				44,912	(252,877)
Ending balance (in shares) at Sep. 30, 2023												211,276,086
Beginning balance at Jun. 30, 2023	4,035,407				222,940				553,610		3,079	$ 1,351				3,383,303				47,065	(175,941)
Beginning balance (in shares) at Jun. 30, 2023												135,058,897
Increase (Decrease) in Stockholders' Equity
Redemption of noncontrolling interests		0								(163)							163
Redemption of noncontrolling interests (in shares)													2,119
Life Storage Merger issuance of common stock and Operating Partnership units (in shares)												76,217,359
Life Storage Merger issuance of common stock and Operating Partnership units	11,602,808								249,470			$ 762				11,352,576
Noncontrolling interest in consolidated joint ventures	5,209										5,209
Net income (loss)	198,856				2,253				8,284		(31)										188,350
Other comprehensive loss	(2,264)								(111)											(2,153)
Distributions to Operating Partnership units held by noncontrolling interests	(14,960)				(2,254)				(12,706)
Dividends paid on common stock	(265,286)																				(265,286)
Issuance of common stock in connection with share based compensation (in shares)												1,253
Issuance of common stock in connection with share based compensation	6,994											$ 0				6,994
Taxes paid upon net settlement of share based compensation (in shares)												(414)
Taxes paid upon net settlement of share based compensation	(63)															(63)
Restricted stock grants cancelled (in shares)												(3,128)
Ending balance at Sep. 30, 2023	15,566,701				222,939				798,384		8,257	$ 2,113				14,742,973				44,912	(252,877)
Ending balance (in shares) at Sep. 30, 2023												211,276,086
Beginning balance at Dec. 31, 2023	$ 15,413,949				222,360				791,754		8,914	$ 2,113				14,750,388				17,435	(379,015)
Beginning balance (in shares) at Dec. 31, 2023	211,278,803											211,278,803
Increase (Decrease) in Stockholders' Equity
Issuance of common stock for share based compensation, exercise of options and taxes paid upon net settlement, net (in shares)												178,944
Issuance of common stock for share based compensation, exercise of options and taxes paid upon net settlement	$ 14,419											$ 2				14,417
Issuance of common stock, net of offering costs (in shares)												2,310
Issuance of common stock, net of offering costs	365															365
Offering costs associated with shelf registration	(522)															(522)
Redemption of noncontrolling interests		0				$ (31,054)				(27,321)			$ 5				58,370
Redemption of noncontrolling interests (in shares)													521,685
Noncontrolling interest in consolidated joint ventures	1,687										1,687
Net income (loss)	622,431				6,073				24,137		27										592,194
Other comprehensive loss	(14,691)								(596)											(14,095)
Distributions to Operating Partnership units held by noncontrolling interests	(47,911)				(6,073)				(41,838)
Dividends paid on common stock	(1,031,044)																				(1,031,044)
Ending balance at Sep. 30, 2024	$ 14,958,683				191,306				746,136		10,628	$ 2,120				14,823,018				3,340	(817,865)
Ending balance (in shares) at Sep. 30, 2024	211,981,742											211,981,742
Beginning balance at Jun. 30, 2024	$ 15,130,840				191,306				757,102		9,800	$ 2,120				14,810,938				27,241	(667,667)
Beginning balance (in shares) at Jun. 30, 2024												211,927,348
Increase (Decrease) in Stockholders' Equity
Issuance of common stock for share based compensation, exercise of options and taxes paid upon net settlement, net (in shares)												10,515
Issuance of common stock for share based compensation, exercise of options and taxes paid upon net settlement	8,224											$ 0				8,224
Offering costs associated with shelf registration	(28)															(28)
Redemption of noncontrolling interests		$ 0								$ (3,884)			$ 0				$ 3,884
Redemption of noncontrolling interests (in shares)													43,879
Noncontrolling interest in consolidated joint ventures	825										825
Net income (loss)	202,945				1,932				7,800		3										193,210
Other comprehensive loss	(24,887)								(986)											(23,901)
Distributions to Operating Partnership units held by noncontrolling interests	(15,828)				(1,932)				(13,896)
Dividends paid on common stock	(343,408)																				(343,408)
Ending balance at Sep. 30, 2024	$ 14,958,683				$ 191,306				$ 746,136		$ 10,628	$ 2,120				$ 14,823,018				$ 3,340	$ (817,865)
Ending balance (in shares) at Sep. 30, 2024	211,981,742											211,981,742

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Noncontrolling Interests and Equity (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Stockholders' Equity [Abstract]
Cash dividends paid per common share (in dollars per share)	$ 1.62	$ 1.62	$ 4.86	$ 4.86	$ 4.86

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities:
Net income (loss)	$ 622,431	$ 623,046
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	586,821	309,914
Amortization of deferred financing costs	13,419	9,716
Non-cash interest expense related to amortization of discount on Life Storage unsecured senior notes	32,563	8,228
Compensation expense related to share-based awards	14,417	19,433
Accrual of interest income added to principal of debt securities and notes receivable	(23,455)	(30,127)
Equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets and sale of a joint venture interest	(13,730)	0
Impairment of Life Storage trade name	51,763	0
Loss on real estate assets held for sale	63,620	0
Distributions from unconsolidated real estate ventures	21,839	11,484
Changes in operating assets and liabilities:
Other assets	45,737	(31,675)
Accounts payable and accrued expenses	45,145	134,310
Other liabilities	18,581	(16,370)
Net cash provided by operating activities	1,479,151	1,037,959
Cash flows from investing activities:
Acquisition of real estate assets and improvements	(361,126)	(197,333)
Life Storage Merger, net of cash acquired	0	(1,182,411)
Development and redevelopment of real estate assets	(100,507)	(66,533)
Proceeds from sale of real estate assets and investments in real estate ventures	4,415	2,132
Investment in unconsolidated real estate entities	(7,175)	(179,258)
Return of investment in unconsolidated real estate ventures	12,999	0
Issuance and purchase of notes receivable	(739,702)	(210,712)
Principal payments received from notes receivable	153,971	73,514
Proceeds from sale of notes receivable	175,335	134,064
Purchase of equipment and fixtures	(15,713)	(9,515)
Net cash used in investing activities	(877,503)	(1,636,052)
Cash flows from financing activities:
Proceeds from unsecured term loans and senior notes and revolving lines of credit	5,542,362	5,194,665
Principal payments on unsecured term loans and senior notes and revolving lines of credit	(6,062,896)	(4,617,755)
Proceeds from issuance of public bonds, net	1,000,000	950,000
Deferred financing costs	(12,633)	(51,359)
Proceeds from share issuances	365	0
Offering costs associated with shelf registration	(522)	0
Contributions from noncontrolling interests	15	0
Dividends paid on common stock	(1,031,044)	(704,069)
Distributions to noncontrolling interests	(48,053)	(43,003)
Net cash (used in) provided by financing activities	(612,406)	723,479
Net (decrease) increase in cash, cash equivalents, and restricted cash	(10,758)	125,386
Cash, cash equivalents, and restricted cash, beginning of the period	105,083	97,735
Cash, cash equivalents, and restricted cash, end of the period	94,325	223,121
Supplemental schedule of cash flow information
Interest paid	381,434	207,569
Income taxes paid	30,635	20,222
Redemption of Operating Partnership units held by noncontrolling interests for common stock
Noncontrolling interests in Operating Partnership	58,375	116,336
Common stock and paid-in capital	(58,375)	(11,336)
Noncontrolling interests in Operating Partnership Note Receivable Payoff	0	(100,000)
OP Unit Redemption - Cash Proceeds	0	(5,000)
Accrued Construction Costs And Capital Expenditures [Abstract]
Acquisition of real estate assets	9,094	6,835
Accounts payable and accrued expenses	(9,094)	(6,835)
Series A Preferred Stock
Cash flows from financing activities:
Redemption of Preferred A Units for cash	$ 0	$ (5,000)

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Statement of Cash Flows [Abstract]
Cash and cash equivalents	$ 88,931	$ 99,062	$ 216,121	$ 92,868
Restricted cash	5,394	6,021	7,000	4,867
Cash, cash equivalents, and restricted cash	$ 94,325	$ 105,083	$ 223,121	$ 97,735

Organization

Organization	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	ORGANIZATION Extra Space Storage Inc. (the “Company”) is a fully integrated, self-administered and self-managed REIT, formed as a Maryland corporation on April 30, 2004, to own, operate, manage, acquire, develop and redevelop professionally managed self-storage properties (“stores”) located throughout the United States. The Company was formed to continue the business of Extra Space Storage LLC and its subsidiaries, which had engaged in the self-storage business since 1977. The Company’s interest in its stores is held through its operating partnership, Extra Space Storage LP (the “Operating Partnership”), which was formed on May 5, 2004. The Company’s primary assets are general partner and limited partner interests in the Operating Partnership, which meets the definition of a variable interest entity and is consolidated. This structure is commonly referred to as an umbrella partnership REIT, or UPREIT. The Company invests in stores by acquiring wholly-owned stores or by acquiring an equity interest in real estate entities. At September 30, 2024, the Company had direct and indirect equity interests in 2,401 stores. In addition, the Company managed 1,461 stores for third parties, bringing the total number of stores which it owns and/or manages to 3,862. These stores are located in 42 states and Washington, D.C. The Company offers tenant reinsurance at its owned and managed stores that insures the value of goods in the storage units and also offers bridge loan financing to certain of its third-party self-storage owners.

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	BASIS OF PRESENTATION The accompanying unaudited condensed consolidated financial statements of the Company are presented on the accrual basis of accounting in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information, and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they may not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the three and nine months ended September 30, 2024 are not necessarily indicative of results that may be expected for the year ending December 31, 2024. The condensed consolidated balance sheet as of December 31, 2023 has been derived from the Company’s audited financial statements as of that date, but does not include all of the information and footnotes required by GAAP for complete financial statements. For further information refer to the consolidated financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the Securities and Exchange Commission. Recently Issued Accounting Standards In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07 – Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amended guidance requires the disclosure of incremental segment information, including significant segment expenses that are regularly provided to the chief operating decision maker (“CODM”) and a reconciliation of segment profit or loss to net income. The title and position of the CODM must also be disclosed, along with how the CODM uses the reported measures to assess segment performance and to allocate resources. Pursuant to this ASU, the footnotes to the Company's consolidated financial statements may include incremental disclosures related to its two reportable segments: (1) self-storage operations and (2) tenant reinsurance. The compliance with this ASU will be required beginning with the Company's annual report on Form 10-K for the year ending December 31, 2024, followed by interim disclosures in quarterly reports on Form 10-Q thereafter, with early adoption permitted. The Company expects to adopt this ASU for its annual report on Form 10-K for the year ending December 31, 2024.

Fair Value Disclosures

Fair Value Disclosures	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Disclosures	FAIR VALUE DISCLOSURES Derivative Financial Instruments Currently, the Company uses interest rate swaps to manage its interest rate risk. The valuation of these instruments is determined using widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash payments and the discounted expected variable cash receipts. The variable cash receipts are based on an expectation of future interest rates (forward curves) derived from observable market interest rate forward curves. The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts and guarantees. In conjunction with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio. Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. However, as of September 30, 2024, the Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments were not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety were classified in Level 2 of the fair value hierarchy. The table below presents the Company’s assets and liabilities measured at fair value on a recurring basis as of September 30, 2024, aggregated by the level in the fair value hierarchy within which those measurements fall. Fair Value Measurements at Reporting Date Using Description Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other assets - Cash flow hedge swap agreements $ — $ 11,716 $ — Other liabilities - Cash flow hedge swap agreements $ — $ 6,093 $ — The Company did not have any significant assets or liabilities that are re-measured on a recurring basis using significant unobservable inputs as of September 30, 2024 or December 31, 2023. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Long-lived assets held for use are evaluated for impairment when events or circumstances indicate there may be impairment. The Company reviews each store at least annually to determine if any such events or circumstances have occurred or exist. The Company focuses on stores where occupancy and/or rental income have decreased by a significant amount. For these stores, the Company determines whether the decrease is temporary or permanent, and whether the store will likely recover the lost occupancy and/or revenue in the short term. In addition, the Company reviews stores in the lease-up stage and compares actual operating results to original projections. When the Company determines that an event that may indicate impairment has occurred, the Company compares the carrying value of the related long-lived assets to the undiscounted future net operating cash flows attributable to the assets. An impairment loss is recorded if the net carrying value of the assets exceeds the undiscounted future net operating cash flows attributable to the assets. The impairment loss recognized equals the excess of net carrying value over the related fair value of the assets. When real estate assets are identified by management as held for sale, the Company discontinues depreciating the assets and estimates the fair value of the assets, net of selling costs. The Company compares the carrying value of the related long-lived assets to the discounted future net operating cash flows attributable to the assets (categorized within Level 3 of the fair value hierarchy). If the estimated fair value, net of selling costs, of the assets that have been identified as held for sale is less than the net carrying value of the assets, the Company would recognize a loss on the assets held for sale. The operations of assets held for sale or sold during the period are presented as part of normal operations. As of September 30, 2024, the Company had 17 stores classified as held for sale which are included in real estate assets, net. Of the 17 stores, nine had an estimated fair value, net of selling costs, of $70,952. During the nine months ended September 30, 2024, the Company recorded a loss of $63,620 as the fair value of these nine stores was less than the net carrying value. The Company assesses annually whether there are any indicators that the value of the Company’s investments in unconsolidated real estate entities may be impaired and when events or circumstances indicate that there may be impairment. An investment is impaired if management’s estimate of the fair value of the investment is less than its carrying value. To the extent impairment has occurred, and is considered to be other than temporary, the loss is measured as the excess of the carrying amount of the investment over the fair value of the investment. The Company evaluates goodwill for impairment at least annually and whenever events, circumstances, and other related factors indicate that the fair value of the related reporting unit may be less than the carrying value. If the fair value of the reporting unit is determined to exceed the aggregate carrying amount, no impairment charge is recorded. Otherwise, an impairment charge is recorded for the amount in which the fair value of the reporting unit exceeds the carrying value. No impairments of goodwill were recorded for any period presented herein. Fair Value of Financial Instruments The carrying values of cash and cash equivalents, restricted cash, receivables, other financial instruments included in other assets, net, accounts payable and accrued expenses, variable-rate notes payable, investments in debt securities and notes receivable, revolving lines of credit and other liabilities reflected in the condensed consolidated balance sheets at September 30, 2024 and December 31, 2023 approximate fair value. Restricted cash is comprised of funds deposited with financial institutions located throughout the United States primarily relating to operating cash reserve for the Company's captive insurance subsidiary and earnest money deposits on potential acquisitions. The fair values of the Company’s fixed-rate notes payable were estimated using the discounted estimated future cash payments to be made on such debt (categorized within Level 3 of the fair value hierarchy); the discount rates used approximated current market rates for loans, or groups of loans, with similar maturities and credit quality. The fair values of the Company’s fixed-rate liabilities were as follows for the periods indicated: September 30, 2024 December 31, 2023 Fair Carrying Fair Carrying Fixed rate debt $ 8,761,624 $ 9,014,590 $ 7,482,054 $ 8,048,605

Acquisitions and Dispositions

Acquisitions and Dispositions	9 Months Ended
	Sep. 30, 2024
Real Estate [Abstract]
Acquisitions and Dispositions	ACQUISITIONS AND DISPOSITIONS The Life Storage Merger On July 20, 2023, the Company closed its merger with Life Storage (the “Life Storage Merger”), which included 757 wholly-owned stores and one consolidated joint venture store. Under the terms of the Life Storage Merger, Life Storage stockholders and holders of units of the Life Storage operating partnership received 0.895 of a share of common stock (or OP Unit, as applicable) of the Company for each issued and outstanding share (or operating partnership unit) of Life Storage they owned for total equity consideration of $11,602,808, based on the Company's closing share price on July 19, 2023. At closing, the Company retired $1,160,000 in balances on Life Storage's line of credit which included $375,000 that Life Storage used to pay off its private placement notes in connection with the closing of the Life Storage Merger. The Company also paid off $32,000 in secured loans. On July 25, 2023, the Company completed obligor exchange offers and consent solicitations (together the “Exchange Offers”) related to Life Storage's various senior notes. Upon the closing of the Exchange Offers, a total of $2,351,100 of Life Storage's senior notes were exchanged for senior notes of the same tenor of Extra Space Storage L.P. The remaining Life Storage senior note balances which were not exchanged total $48,900 and no longer have any financial reporting requirements or covenants. Consideration and Purchase Price Allocation The Life Storage Merger was accounted for as an asset acquisition in accordance with ASC Topic 805 which requires that the cost of an acquisition be allocated on a relative fair value basis to the assets acquired and the liabilities assumed. The following table summarizes the fair value of total consideration transferred in the Life Storage Merger: Consideration Type July 20, 2023 Common stock $ 11,353,338 OP units 249,470 Cash for payoff of Life Storage credit facility and debt 1,192,000 Transaction Costs 55,318 Total consideration $ 12,850,127 The following table summarizes the estimated fair values assigned to the assets acquired and liabilities assumed: July 20, 2023 Real estate assets $ 14,587,735 Equity investment in joint venture partnerships 325,250 Cash and other assets 107,423 Intangible assets - other 82,000 Trade name 50,000 Unsecured senior notes (2,106,866) Accounts payable, accrued expenses and other liabilities (191,077) Noncontrolling interests (4,338) Fair value of net assets acquired $ 12,850,127 Fair Value Measurement The estimated fair values of assets acquired and liabilities assumed were primarily based on information that was available as of the closing date of the Life Storage Merger. The methodology used to estimate the fair values to apply purchase accounting and the ongoing financial statement impact, if any, are summarized below. • Real estate assets – Real estate assets acquired were recorded at fair value using standard valuation methodologies, including the cost and market approaches. The remaining useful lives for real estate assets, excluding land, were reset to 39 years. Tenant relationships for storage leases were recorded at fair value based on estimated costs the Company avoided to replace them. Tenant relationships are amortized to expense over 18 months, which is based on the Company’s historical experience with turnover in its stores. • Equity investment in joint venture partnerships – Equity investment in joint venture partnerships were recorded at fair value based on a direct capitalization of net operating income. • Intangible assets - other – Customer relationships relating to tenant reinsurance contracts were recorded at fair value based on the income approach which estimates the potential revenue loss the Company avoided to replace them. These assets are amortized to expense over 36 months, which is based on the Company’s historical experience with average length of stay for tenants. • Trade name – Trade names were recorded at fair value based on royalty payments avoided had the trade name been owned by a third party. This is determined using market royalty rates and a discounted cash flow analysis under the relief-from-royalty method. This method incorporates various assumptions, including projected revenue growth rates, the terminal growth rate, the royalty rate to be applied, and the discount rate utilized. The trade name is an indefinite lived asset and as such is not amortized. During the three months ended September 30, 2024, the Company decided to operate all stores under a single brand. As a result of that decision, the Company deemed the Life Storage trade name intangible asset to be impaired and recognized a loss for the full value of the asset. • Unsecured senior notes – Unsecured senior notes were recorded at fair value using readily available market data. The below-market value of debt is recorded as a debt discount and reported as a reduction of the unsecured senior notes, net balance on the condensed consolidated balance sheets. The discount is amortized using the effective interest method as an increase to interest expense over the remaining terms of the unsecured senior notes. • Other assets and liabilities – The carrying values of cash, accounts receivable, prepaids and other assets, accounts payable, accrued expenses and other liabilities represented the fair values. Store Acquisitions The following table shows the Company’s acquisitions of stores for the three and nine months ended September 30, 2024 and 2023. The table excludes purchases of raw land and improvements made to existing assets. All store acquisitions are considered asset acquisitions under ASU 2017-01, “ Business Combinations (Topic 805): Clarifying the Definition of a Business .” Total Period Number of Stores Cash Paid Loan Assumed Finance Lease Liability Investments in Real Estate Ventures Net Liabilities/ (Assets) Assumed Value of Equity Issued Real estate assets Q3 2024 11 $ 159,196 $ — $ — $ — $ 1,431 $ — $ 160,627 Q2 2024 3 27,644 — — — 97 $ — 27,741 Q1 2024 6 35,084 — — — 171 $ — 35,255 Total 2024 20 $ 221,924 $ — $ — $ — $ 1,699 $ — $ 223,623 Q3 2023 3 $ 18,578 $ — $ — $ — $ 86 $ — $ 18,664 Q2 2023 3 32,888 — — — 26 — 32,914 Q1 2023 1 13,111 — — — 6 — 13,117 Total 2023 7 $ 64,577 $ — $ — $ — $ 118 $ — $ 64,695

Real Estate Assets

Real Estate Assets	9 Months Ended
	Sep. 30, 2024
Real Estate [Abstract]
Real Estate Assets	REAL ESTATE ASSETS The components of real estate assets are summarized as follows: September 30, 2024 December 31, 2023 Land $ 4,923,702 $ 4,904,705 Buildings, improvements and other intangibles 22,032,745 21,664,224 Right of use asset - finance lease 143,286 143,842 Intangible assets - tenant relationships 322,771 321,019 Intangible lease rights 27,743 27,743 27,450,247 27,061,533 Less: accumulated depreciation and amortization (3,168,088) (2,624,405) Net operating real estate assets 24,282,159 24,437,128 Real estate under development/redevelopment 103,333 118,745 Real estate assets, net $ 24,385,492 $ 24,555,873 Real estate assets held for sale included in real estate assets, net $ 131,527 $ — In September 2024, the Company amended existing triple-net lease agreements for land and buildings related to 27 stores that had initially been entered into in June and August 2019. The Company also entered into new triple-net lease agreements for land and buildings related to 12 additional stores. Both the initial 27 stores and the additional 12 stores added to the triple net lease structure are categorized as operating leases and have been presented in real estate assets - operating lease right-of-use assets and operating lease liabilities on the Company's condensed consolidated balance sheets. As of September 30, 2024, the Company had 17 stores classified as held for sale which are included in real estate assets, net. Of the 17 stores, nine had an estimated fair value, net of selling costs, less than the carrying value of the assets. During the three and nine months ended September 30, 2024, the Company recorded estimated losses of $8,961 and $63,620, respectively, in loss on real estate assets held for sale on the Company's condensed consolidated statements of operations. Assets held for sale are included in the self-storage operations segment of the Company’s segment information.

Other Assets

Other Assets	9 Months Ended
	Sep. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	OTHER ASSETS The components of other assets are summarized as follows: September 30, 2024 December 31, 2023 Goodwill $ 170,811 $ 170,811 Receivables, net 112,748 134,716 Prepaid expenses and deposits 97,521 85,153 Other intangible assets, net 39,498 66,332 Trade name — 50,000 Fair value of interest rate swaps 11,716 26,183 Equipment and fixtures, net 50,065 48,697 Deferred line of credit financing costs, net 8,108 9,787 Restricted cash 5,394 6,021 $ 495,861 $ 597,700 During the three months ended September 30, 2024, the Company decided to operate all stores under a single brand. As a result of that decision, the Company deemed the Life Storage trade name intangible asset to be impaired and recognized a loss for the full value of the asset. A loss of $51,763 for the write-off of the asset and related costs has been recorded in impairment of Life Storage trade name on the Company's condensed consolidated statements of operations for the three months ended September 30, 2024. The trade name was originally recorded at fair value based on royalty payments avoided had the trade name been owned by a third party. This was determined using market royalty rates and a discounted cash flow analysis under the relief-from-royalty method. Intangible assets are included in the self-storage operations segment of the Company’s segment information.

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Earnings Per Common Share	EARNINGS PER COMMON SHARE Basic earnings per common share is computed using the two-class method by dividing net income attributable to common stockholders by the weighted average number of common shares outstanding during the period. All outstanding unvested restricted stock awards contain rights to non-forfeitable dividends and participate in undistributed earnings with common stockholders; accordingly, they are considered participating securities that are included in the two-class method. Diluted earnings per common share measures the performance of the Company over the reporting period while giving effect to all potential common shares that were dilutive and outstanding during the period. The denominator includes the weighted average number of basic shares and the number of additional common shares that would have been outstanding if the potential common shares that were dilutive had been issued, and is calculated using the two-class, treasury stock or if-converted method, whichever is most dilutive. Potential common shares are securities (such as options, Series A Participating Redeemable Preferred Units (“Series A Units”), Series B Redeemable Preferred Units (“Series B Units”), Series D Redeemable Preferred Units (“Series D Units” and, together with the Series A Units and Series B Units, the “Preferred OP Units”) and common Operating Partnership units (“OP Units”)) that do not have a current right to participate in earnings of the Company but could do so in the future by virtue of their option, redemption or conversion right. In computing the dilutive effect of convertible securities, net income is adjusted to add back any changes in earnings in the period associated with the convertible security. The numerator also is adjusted for the effects of any other non-discretionary changes in income or loss that would result from the assumed conversion of those potential common shares. In computing diluted earnings per common share, only potential common shares that are dilutive (i.e. those that reduce earnings per common share) are included. For the purposes of computing the diluted impact of the potential exchange of the Preferred Operating Partnership units for common shares upon redemption, where the Company has the option to redeem in cash or shares and where the Company has stated the intent and ability to settle the redemption in shares, the Company divided the total value of the Preferred Operating Partnership units by the average share price for the period presented. The average share price for the three months ended September 30, 2024 and 2023 was $168.78 and $134.24, respectively. The following table presents the number of Common and Preferred Operating Partnership units as if converted into potential common shares that were excluded from the computation of earnings per share as their effect would have been anti-dilutive. For the Three Months Ended September 30, For the Nine Months Ended September 30, 2024 2023 2024 2023 Equivalent Shares (if converted) Equivalent Shares (if converted) Equivalent Shares (if converted) Equivalent Shares (if converted) Common OP Units — 8,541,775 — 7,661,885 Series B Units 198,887 250,061 218,529 228,029 Series D Units 934,585 1,409,198 1,111,927 1,287,256 1,133,472 10,201,034 1,330,456 9,177,170 The computation of earnings per common share is as follows for the periods presented: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2024 2023 2024 2023 Net income attributable to common stockholders $ 193,210 $ 188,350 $ 592,194 $ 587,064 Earnings and dividends allocated to participating securities (392) (304) (1,141) (931) Earnings for basic computations 192,818 188,046 591,053 586,133 Income allocated to noncontrolling interest - Preferred Operating Partnership Units and Operating Partnership Units 7,800 — 24,136 — Net income for diluted computations $ 200,618 $ 188,046 $ 615,189 $ 586,133 Weighted average common shares outstanding: Average number of common shares outstanding - basic 211,698,436 195,324,444 211,522,578 155,112,071 OP Units 8,597,656 — 8,651,915 — Shares related to dilutive stock options 2,778 3,576 3,199 4,078 Average number of common shares outstanding - diluted 220,298,870 195,328,020 220,177,692 155,116,149 Earnings per common share Basic $ 0.91 $ 0.96 $ 2.79 $ 3.78 Diluted $ 0.91 $ 0.96 $ 2.79 $ 3.78

Investments in Unconsolidated R

Investments in Unconsolidated Real Estate Entities	9 Months Ended
	Sep. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Real Estate Entities	INVESTMENTS IN UNCONSOLIDATED REAL ESTATE ENTITIES Investments in unconsolidated real estate entities and cash distributions in unconsolidated real estate ventures represent the Company's interest in preferred stock of SmartStop Self Storage REIT, Inc. (“SmartStop”) and Strategic Storage Trust VI, Inc. (“Strategic Storage”), an affiliate of SmartStop, and the Company's noncontrolling interest in real estate joint ventures. The Company accounts for its investments in SmartStop and Strategic Storage preferred stock, which do not have a readily determinable fair value, at the transaction price less impairment, if any. The Company accounts for its investments in joint ventures using the equity method of accounting. The Company initially records these investments at cost and subsequently adjusts for cash contributions, distributions and net equity in income or loss, which is allocated in accordance with the provisions of the applicable partnership or joint venture agreement. In these joint ventures, the Company and the joint venture partner generally receive a preferred return on their invested capital. To the extent that cash or profits in excess of these preferred returns are generated through operations or capital transactions, the Company would receive a higher percentage of the excess cash or profits, as applicable, than its equity interest. The Company separately reports investments with net equity less than zero in cash distributions in unconsolidated real estate ventures in the condensed consolidated balance sheets. The net equity of certain joint ventures is less than zero because distributions have exceeded the Company's investment in and share of income from these joint ventures. This is generally the result of financing distributions, capital events or operating distributions that are usually greater than net income, as net income includes non-cash charges for depreciation and amortization while distributions do not. Net investments in unconsolidated real estate entities and cash distributions in unconsolidated real estate ventures consist of the following: Number of Stores Equity Ownership % Excess Profit % (1) September 30, December 31, 2024 2023 PRISA Self Storage LLC 85 4% 4% $ 9,110 $ 9,435 HF1 Sovran HHF Storage Holdings LLC 37 20% 20% 102,901 105,339 Storage Portfolio II JV LLC 36 10% 30% (9,219) (8,314) Storage Portfolio IV JV LLC 32 10% 30% 47,491 48,184 Storage Portfolio I LLC 24 34% 49% (43,430) (42,487) PR II EXR JV LLC 23 25% 25% 106,456 108,160 HF2 Sovran HHF Storage Holdings II LLC 22 15% 15% 41,039 41,613 HF5 Life Storage-HIERS Storage LLC 17 20% 20% 25,450 26,051 HF6 191 V Life Storage Holdings LLC 17 20% 20% 11,315 12,702 ESS-CA TIVS JV LP 16 55% 55%-65% 27,794 29,128 VRS Self Storage, LLC 16 45% 54% (17,312) (16,386) HF10 Life Storage HHF Wasatch Holdings LLC 16 20% 20% 19,581 20,019 Other unconsolidated real estate ventures (2) (3) 119 10%-50% 10%-50% 314,864 317,104 SmartStop Self Storage REIT, Inc. Preferred Stock (4) n/a n/a n/a 200,000 200,000 Strategic Storage Trust VI, Inc. Preferred Stock (5) n/a n/a n/a 150,000 150,000 Net Investments in and Cash distributions in unconsolidated real estate entities 460 $ 986,040 $ 1,000,548 (1) Includes pro-rata equity ownership share and promoted interest. (2) In August 2024, the ESS Bristol Investments LLC unconsolidated joint venture sold five of its eight stores to another of the Company's unconsolidated joint ventures, and the Company recognized a gain of $10,324 for its pro rata share of the transaction. The Company then acquired its partner's membership interest in the remaining three stores held by ESS Bristol Investments LLC, which is now presented under real estate assets, net on the Company's condensed consolidated balance sheets. (3) In September 2024, the Company sold its membership interest in the Alan Jathoo JV LLC unconsolidated joint venture, which held nine stores, to its partner in such joint venture and recognized a gain of $3,406 on the transaction. This gain and the gain from the ESS Bristol Investments LLC transaction are presented in equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets and sale of a joint venture interest on the Company's condensed consolidated statements of operations for the three months ended September 30, 2024. (4) In October 2019, the Company invested $200,000 in shares of convertible preferred stock of SmartStop with a dividend rate of 6.25% per annum, subject to increase after five years. The preferred shares are generally not redeemable for five years, except in the case of a change of control or initial listing of SmartStop. Dividend income from this investment is included on the equity in earnings and dividend income from unconsolidated real estate entities line on the Company's condensed consolidated statements of operations. (5) In May 2023, the Company invested $150,000 in shares of convertible preferred stock of Strategic Storage with a dividend rate of 8.35% per annum, subject to increase after five years. The preferred shares are generally not redeemable for three years, except in the case of a change of control or initial listing of Strategic Storage. Dividend income from this investment is included on the equity in earnings and dividend income from unconsolidated real estate entities on the Company's condensed consolidated statements of operations.

Investments in Debt Securities

Investments in Debt Securities and Notes Receivable	9 Months Ended
	Sep. 30, 2024
Investments, Debt and Equity Securities [Abstract]
Investments in Debt Securities and Notes Receivable	INVESTMENTS IN DEBT SECURITIES AND NOTES RECEIVABLE Investments in debt securities and notes receivable consists of the Company's investment in mandatorily redeemable preferred stock of Jernigan Capital, Inc. (“JCAP”) in connection with JCAP's acquisition by affiliates of NexPoint Advisors, L.P. (“NexPoint”) and receivables due to the Company under its bridge loan program. Information about these balances is as follows: September 30, 2024 December 31, 2023 Debt securities - Preferred Stock $ 300,000 $ 300,000 Notes Receivable - Bridge Loans 1,032,244 594,727 Dividends and Interest Receivable 6,375 10,042 $ 1,338,619 $ 904,769 In November 2020, the Company invested $300,000 in the preferred stock of JCAP in connection with the acquisition of JCAP by NexPoint. This investment consisted of 200,000 Series A Preferred Shares valued at a total of $200,000, and 100,000 Series B Preferred Shares valued at a total of $100,000. In December 2022, the Company completed a modification with NexPoint Storage Partners (as successor in interest to JCAP) that exchanged the Series A and Series B Preferred Shares for 300,000 Series D Preferred Shares, valued at a total of $300,000. The Series D Preferred Shares are mandatorily redeemable after six years from the modification in December 2022, with two one-year extension options. NexPoint may redeem the Series D Preferred Shares at any time, subject to certain prepayment penalties. The Company accounts for the Series D Preferred Shares as a held to maturity debt security at amortized cost. The Series D Preferred Shares have an initial dividend rate of 8.5%. If the investment is not retired after six years, the preferred dividends increase annually. The Company offers bridge loan financing to certain of its third-party self-storage owners. These notes receivable consist of mortgage loans receivable, which are collateralized by self-storage properties that the Company manages, and mezzanine loans receivable, which are secured by equity interest pledges. As of September 30, 2024, 71% of the notes held are mortgage receivables. The Company intends to sell a portion of the mortgage receivables. These notes receivable typically have a term of three years with two one-year extensions and have variable interest rates. During the nine months ended September 30, 2024, the Company sold a total principal amount of $175,335 of its mortgage bridge loans receivable to third parties for a total of $175,335 in cash, closed on $636,215 in initial loan draws and recorded $39,709 of draws for interest payments.

Debt

Debt	9 Months Ended
	Sep. 30, 2024
Debt Disclosure [Abstract]
Debt	DEBT The components of term debt are summarized as follows: Term Debt September 30, 2024 December 31, 2023 Secured notes payable (1) $ 1,018,209 $ 1,279,105 Unsecured term loans 2,200,000 2,660,000 Unsecured senior notes 7,725,000 6,725,000 Total 10,943,209 10,664,105 Less: Discount on unsecured senior notes (2) (241,786) (274,350) Less: Unamortized debt issuance costs (57,593) (55,007) Total $ 10,643,830 $ 10,334,748 (1) The loans are collateralized by mortgages on real estate assets and the assignment of rents. (2) Unsecured senior notes from the Life Storage Merger were recorded at fair value, resulting in a discount to be amortized over the term of the debt. The following table summarizes the scheduled maturities of term debt, excluding available extensions, at September 30, 2024: Year Amount 2024 $ — 2025 782,722 2026 1,409,525 2027 1,312,689 2028 1,328,100 2029 1,516,807 2030 1,343,366 2031 1,650,000 2032 600,000 Thereafter 1,000,000 $ 10,943,209 All of the Company’s lines of credit are guaranteed by the Company. The following table presents information on the Company’s lines of credit, the proceeds of which are used to repay debt and for general corporate purposes, for the periods indicated: As of September 30, 2024 Revolving Lines of Credit Amount Drawn Capacity Interest Rate Maturity Basis Rate (1) Credit Line 1 (2) $ 55,000 $ 140,000 6.31% 7/1/2026 SOFR plus 1.35% Credit Line 2 (3)(4) 829,000 2,000,000 5.84% 6/22/2027 SOFR plus 0.875% $ 884,000 $ 2,140,000 (1) Daily Simple Secured Overnight Financing Rate (“SOFR”) (2) Secured by mortgages on certain real estate assets. On January 13, 2023, the maturity date was extended to July 1, 2026 with one extension of one (3) Unsecured. On June 22, 2023, the maturity date was extended to June 22, 2027 with two six (4) Basis Rate as of September 30, 2024. Rate is subject to change based on the Company's investment grade rating. On June 22, 2023, the Company entered into the Third Amended and Restated Credit Agreement (the “Credit Agreement”). Pursuant to the terms of the Credit Agreement, the Company may request an extension of the term of the revolving credit facility for up to two additional periods of six months each, after satisfying certain conditions. As of September 30, 2024, amounts outstanding under the revolving credit facility bore interest at floating rates, at the Company’s option, equal to either (i) Adjusted Term or Daily Simple SOFR plus the applicable margin or (ii) the applicable base rate which is the applicable margin plus the highest of (a) 0.0%, (b) the federal funds rate plus 0.50%, (c) U.S. Bank’s prime rate or (d) the SOFR rate plus 1.00%. Per the Credit Agreement, the applicable SOFR rate margin and applicable base rate margin are based on the Company’s achieved debt rating, with the SOFR rate margin ranging from 0.7% to 2.2% per annum and the applicable base rate margin ranging from 0.00% to 1.20% per annum. The Credit Agreement is guaranteed by the Company and is not secured by any assets of the Company. The Company's unsecured debt is subject to certain financial covenants. As of September 30, 2024, the Company was in compliance with all of its financial covenants. As of September 30, 2024, the Company’s percentage of fixed-rate debt to total debt was 78.3%. The weighted average interest rates of the Company’s fixed and variable-rate debt were 4.0% and 6.0%, respectively. The combined weighted average interest rate was 4.5%.

Derivatives

Derivatives	9 Months Ended
	Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	DERIVATIVES The Company is exposed to certain risk arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity and credit risk, primarily by managing the amount, sources and duration of its debt funding and the use of derivative financial instruments. Specifically, the Company enters into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing and duration of the Company’s known or expected cash payments principally related to the Company’s borrowings. Cash Flow Hedges of Interest Rate Risk The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish these objectives, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive income (“OCI”) and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. A portion of these changes is excluded from accumulated other comprehensive income as it is allocated to noncontrolling interests. During the three and nine months ended September 30, 2024 and 2023, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt. In the coming 12 months, the Company estimates that $7,681 will be reclassified as an increase to interest income. The Company held 14 active derivative financial instruments, which had a total current notional amount of $1,382,568 as of September 30, 2024 and two forward-starting derivative financial instruments with effective dates of October 31, 2024 and July 14, 2025. Fair Values of Derivative Instruments The table below presents the fair values of the Company’s derivative financial instruments as well as their classification on the condensed consolidated balance sheets: Asset / Liability Derivatives Derivatives designated as hedging instruments: September 30, 2024 December 31, 2023 Other assets $ 11,716 $ 26,183 Other liabilities $ 6,093 $ 5,030 Effect of Derivative Instruments The table below presents the effect of the Company’s derivative financial instruments on the condensed consolidated statements of operations for the periods presented. No tax effect has been presented as the derivative instruments are held by the Company: Gain (loss) recognized in OCI for the Three Months Ended September 30, Location of amounts reclassified from OCI into income Gain (loss) reclassified from OCI for the Three Months Ended September 30, Type 2024 2023 2024 2023 Swap Agreements $ (17,931) $ 9,146 Interest expense $ 6,965 $ 11,415 Gain (loss) recognized in OCI for the Nine Months Ended September 30, Location of amounts reclassified from OCI into income Gain (loss) reclassified from OCI for the Nine Months Ended September 30, Type 2024 2023 2024 2023 Swap Agreements $ 7,363 $ 27,212 Interest expense $ 22,042 $ 31,398 Credit-Risk-Related Contingent Features The Company has agreements with some of its derivative counterparties that contain provisions pursuant to which the Company could be declared in default of its derivative obligations if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender. The Company also has an agreement with some of its derivative counterparties that incorporates the loan covenant provisions of the Company’s indebtedness with a lender affiliate of the derivative counterparty. Failure to comply with the loan covenant provisions would result in the Company being in default on any derivative instrument obligations covered by the agreement.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2024
Stockholders' Equity Note [Abstract]
Stockholders' Equity	STOCKHOLDERS’ EQUITY On April 15, 2024, the Company filed its $800,000 “at the market” equity program with the Securities and Exchange Commission using a shelf registration statement on Form S-3, and entered into an equity distribution agreement with nine sales agents. No shares have been sold under the current “at the market” equity program, and no shares were sold under the previous “at the market” equity program, which spanned from August 9, 2021 through April 14, 2024. On November 13, 2023, the Company's board of directors authorized a share repurchase program allowing for the repurchase of shares with an aggregate value up to $500,000. During the year ended December 31, 2023 and the nine months ended September 30, 2024, no shares were repurchased. As of September 30, 2024, the Company had remaining authorization to repurchase shares with an aggregate value up to $500,000. On July 20, 2023, the Company issued 76,217,359 shares of its common stock at $148.96 for a total value of $11,353,338 as part of the Life Storage Merger. See Acquisitions and Dispositions note above.

Noncontrolling Interest Represe

Noncontrolling Interest Represented by Preferred Operating Partnership Units	9 Months Ended
	Sep. 30, 2024
Noncontrolling Interest [Abstract]
Noncontrolling Interest Represented by Preferred Operating Partnership Units	NONCONTROLLING INTEREST REPRESENTED BY PREFERRED OPERATING PARTNERSHIP UNITS Classification of Noncontrolling Interests GAAP requires a company to present ownership interests in subsidiaries held by parties other than the company in the consolidated financial statements within the equity section, but separate from the company’s equity. It also requires the amount of consolidated net income attributable to the parent and to the noncontrolling interest to be clearly identified and presented on the face of the consolidated statement of operations and requires changes in ownership interest to be accounted for similarly as equity transactions. If noncontrolling interests are determined to be redeemable, they are to be carried at their redemption value as of the balance sheet date and reported as temporary equity. The Company has evaluated the terms of the Operating Partnership’s preferred units and classifies the noncontrolling interest represented by such preferred units as stockholders’ equity in the accompanying condensed consolidated balance sheets. The Company will periodically evaluate individual noncontrolling interests for the ability to continue to recognize the noncontrolling interest as permanent equity in the condensed consolidated balance sheets. Any noncontrolling interests that fail to qualify as permanent equity will be reclassified as temporary equity and adjusted to the greater of (1) the carrying amount and (2) the redemption value as of the end of the period in which the determination is made. At September 30, 2024 and December 31, 2023, the noncontrolling interests represented by the Preferred OP Units qualified for classification as permanent equity on the Company's condensed consolidated balance sheets. The partnership agreement of the Operating Partnership (as amended, the “Partnership Agreement”) provides for the designation and issuance of the OP Units. The balances for each of the specific Preferred OP Units as presented in the Statement of Noncontrolling Interests and Equity as of the periods indicated are as follows: September 30, 2024 December 31, 2023 Series B Units $ 33,567 $ 33,567 Series D Units 157,739 188,793 $ 191,306 $ 222,360 Series A Participating Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series A Units. The Series A Units have priority over all other partnership interests of the Operating Partnership with respect to distributions and liquidation. As of September 30, 2024 and December 31, 2023, there were no outstanding Series A Units. Series B Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series B Units. The Series B Units rank junior to the Series A Units, on parity with the Series C Units and Series D Units, and senior to all other partnership interests of the Operating Partnership with respect to distributions and liquidation. The Series B Units were issued in 2013 and 2014. The Series B Units have a liquidation value of $25.00 per unit for a fixed liquidation value of $33,567 which represents 1,342,727 Series B Units. Holders of the Series B Units receive distributions at an annual rate of 6.0%. These distributions are cumulative. The Series B Units became redeemable at the option of the holder on the first anniversary of the date of issuance, which redemption obligation may be satisfied at the Company’s option in cash or shares of its common stock. Series C Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series C Units. The Series C Units ranked junior to the Series A Units, on parity with the Series B Units and Series D Units, and senior to all other partnership interests of the Operating Partnership with respect to distributions and liquidation. As of September 30, 2024 and December 31, 2023, there were no outstanding Series C Units. Series D Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series D Units. The Series D Units rank junior to the Series A Units, on parity with the Series B Units and Series C Units, and senior to all other partnership interests of the Operating Partnership with respect to distributions and liquidation. The Series D Units have a liquidation value of $25.00 per unit, for a fixed liquidation value of $157,739, which represents 6,309,567 Series D Units. Holders of the Series D Units receive distributions at an annual rate between 3.0% and 5.0%. These distributions are cumulative. The Series D Units become redeemable at the option of the holder on the first anniversary of the date of issuance, which redemption obligation may be satisfied at the Company’s option in cash or shares of its common stock. In addition, certain of the Series D Units are exchangeable for OP Units at the option of the holder until the tenth anniversary of the date of issuance, with the number of OP Units to be issued equal to $25.00 per Series D Unit, divided by the value of a share of common stock as of the exchange date. During the nine months ended September 30, 2024, 1,242,168 Series D Units were redeemed for 213,661 shares of common stock. Noncontrolling Interest in Operating Partnership The Company’s interest in its stores is held through the Operating Partnership. Between its general partner and limited partner interests, the Company held a 95.6% ownership interest in the Operating Partnership as of September 30, 2024. The remaining ownership interests in the Operating Partnership (including Preferred OP Units) of 4.4% are held by certain former owners of assets acquired by the Operating Partnership. As of September 30, 2024 and December 31, 2023, the noncontrolling interests in the Operating Partnership are shown on the balance sheet net of a note receivable of $1,900 because a borrower under the note receivable is also a holder of OP Units. This note receivable originated in December 2014, bears interest at 5.0% per annum and matures on December 15, 2024. The noncontrolling interest in the Operating Partnership represents OP Units that are not owned by the Company. OP Units are redeemable at the option of the holder, which redemption may be satisfied at the Company's option in cash, based upon the fair market value of an equivalent number of shares of the Company’s common stock (based on the ten-day average trading price) at the time of the redemption, or shares of the Company's common stock on a one-for-one basis, subject to anti-dilution adjustments provided in the Partnership Agreement. As of September 30, 2024, the ten-day average closing price of the Company's common stock was $180.16 and there were 8,577,570 OP Units outstanding. Assuming that all of the OP Unit holders exercised their right to redeem all of their OP Units on September 30, 2024 and the Company elected to pay the OP Unit holders cash, the Company would have paid $1,545,335 in cash consideration to redeem the units. OP Unit activity is summarized as follows for the periods presented: For the Nine Months Ended September 30, 2024 2023 OP Units redeemed for common stock 308,024 — OP Units issued in conjunction with business combination and acquisitions — 1,674,748 Value of OP Units issued in conjunction with business combination and acquisitions $ — $ 249,470 GAAP requires a company to present ownership interests in subsidiaries held by parties other than the company in the consolidated financial statements within the equity section, but separate from the company’s equity. It also requires the amount of consolidated net income attributable to the parent and to the noncontrolling interest to be clearly identified and presented on the face of the consolidated statement of operations, and requires changes in ownership interest to be accounted for similarly as equity transactions. If noncontrolling interests are determined to be redeemable, they are to be carried at their redemption value as of the balance sheet date and reported as temporary equity. The Company has evaluated the terms of the OP Units and classifies the noncontrolling interest represented by the OP Units as stockholders’ equity in the accompanying condensed consolidated balance sheets. The Company will periodically evaluate individual noncontrolling interests for the ability to continue to recognize the noncontrolling amount as permanent equity in the condensed consolidated balance sheets. Any noncontrolling interests that fail to qualify as permanent equity will be reclassified as temporary equity and adjusted to the greater of (1) the carrying amount, or (2) its redemption value as of the end of the period in which the determination is made. Other Noncontrolling Interests Other noncontrolling interests represent the ownership interest of partners in nine consolidated joint ventures as of September 30, 2024. There are a total of 13 stores in consolidated joint ventures, seven of which are operating and the other six of which are under development. The voting interests of the partners are 17.0% or less. Based on the facts and circumstances of each of the Company’s joint ventures, the Company has determined that one of the joint ventures at September 30, 2024 was a variable interest entity (“VIE”) in accordance with ASC 810, “Consolidation.” The Company has consolidated that joint venture as it was determined that the Company has the power to direct the activities of the joint venture and is the primary beneficiary of the joint venture.

Noncontrolling Interest in Oper

Noncontrolling Interest in Operating Partnership and Other Noncontrolling Interests	9 Months Ended
	Sep. 30, 2024
Noncontrolling Interest [Abstract]
Noncontrolling Interest in Operating Partnership and Other Noncontrolling Interests	NONCONTROLLING INTEREST REPRESENTED BY PREFERRED OPERATING PARTNERSHIP UNITS Classification of Noncontrolling Interests GAAP requires a company to present ownership interests in subsidiaries held by parties other than the company in the consolidated financial statements within the equity section, but separate from the company’s equity. It also requires the amount of consolidated net income attributable to the parent and to the noncontrolling interest to be clearly identified and presented on the face of the consolidated statement of operations and requires changes in ownership interest to be accounted for similarly as equity transactions. If noncontrolling interests are determined to be redeemable, they are to be carried at their redemption value as of the balance sheet date and reported as temporary equity. The Company has evaluated the terms of the Operating Partnership’s preferred units and classifies the noncontrolling interest represented by such preferred units as stockholders’ equity in the accompanying condensed consolidated balance sheets. The Company will periodically evaluate individual noncontrolling interests for the ability to continue to recognize the noncontrolling interest as permanent equity in the condensed consolidated balance sheets. Any noncontrolling interests that fail to qualify as permanent equity will be reclassified as temporary equity and adjusted to the greater of (1) the carrying amount and (2) the redemption value as of the end of the period in which the determination is made. At September 30, 2024 and December 31, 2023, the noncontrolling interests represented by the Preferred OP Units qualified for classification as permanent equity on the Company's condensed consolidated balance sheets. The partnership agreement of the Operating Partnership (as amended, the “Partnership Agreement”) provides for the designation and issuance of the OP Units. The balances for each of the specific Preferred OP Units as presented in the Statement of Noncontrolling Interests and Equity as of the periods indicated are as follows: September 30, 2024 December 31, 2023 Series B Units $ 33,567 $ 33,567 Series D Units 157,739 188,793 $ 191,306 $ 222,360 Series A Participating Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series A Units. The Series A Units have priority over all other partnership interests of the Operating Partnership with respect to distributions and liquidation. As of September 30, 2024 and December 31, 2023, there were no outstanding Series A Units. Series B Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series B Units. The Series B Units rank junior to the Series A Units, on parity with the Series C Units and Series D Units, and senior to all other partnership interests of the Operating Partnership with respect to distributions and liquidation. The Series B Units were issued in 2013 and 2014. The Series B Units have a liquidation value of $25.00 per unit for a fixed liquidation value of $33,567 which represents 1,342,727 Series B Units. Holders of the Series B Units receive distributions at an annual rate of 6.0%. These distributions are cumulative. The Series B Units became redeemable at the option of the holder on the first anniversary of the date of issuance, which redemption obligation may be satisfied at the Company’s option in cash or shares of its common stock. Series C Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series C Units. The Series C Units ranked junior to the Series A Units, on parity with the Series B Units and Series D Units, and senior to all other partnership interests of the Operating Partnership with respect to distributions and liquidation. As of September 30, 2024 and December 31, 2023, there were no outstanding Series C Units. Series D Redeemable Preferred Units The Partnership Agreement provides for the designation and issuance of the Series D Units. The Series D Units rank junior to the Series A Units, on parity with the Series B Units and Series C Units, and senior to all other partnership interests of the Operating Partnership with respect to distributions and liquidation. The Series D Units have a liquidation value of $25.00 per unit, for a fixed liquidation value of $157,739, which represents 6,309,567 Series D Units. Holders of the Series D Units receive distributions at an annual rate between 3.0% and 5.0%. These distributions are cumulative. The Series D Units become redeemable at the option of the holder on the first anniversary of the date of issuance, which redemption obligation may be satisfied at the Company’s option in cash or shares of its common stock. In addition, certain of the Series D Units are exchangeable for OP Units at the option of the holder until the tenth anniversary of the date of issuance, with the number of OP Units to be issued equal to $25.00 per Series D Unit, divided by the value of a share of common stock as of the exchange date. During the nine months ended September 30, 2024, 1,242,168 Series D Units were redeemed for 213,661 shares of common stock. Noncontrolling Interest in Operating Partnership The Company’s interest in its stores is held through the Operating Partnership. Between its general partner and limited partner interests, the Company held a 95.6% ownership interest in the Operating Partnership as of September 30, 2024. The remaining ownership interests in the Operating Partnership (including Preferred OP Units) of 4.4% are held by certain former owners of assets acquired by the Operating Partnership. As of September 30, 2024 and December 31, 2023, the noncontrolling interests in the Operating Partnership are shown on the balance sheet net of a note receivable of $1,900 because a borrower under the note receivable is also a holder of OP Units. This note receivable originated in December 2014, bears interest at 5.0% per annum and matures on December 15, 2024. The noncontrolling interest in the Operating Partnership represents OP Units that are not owned by the Company. OP Units are redeemable at the option of the holder, which redemption may be satisfied at the Company's option in cash, based upon the fair market value of an equivalent number of shares of the Company’s common stock (based on the ten-day average trading price) at the time of the redemption, or shares of the Company's common stock on a one-for-one basis, subject to anti-dilution adjustments provided in the Partnership Agreement. As of September 30, 2024, the ten-day average closing price of the Company's common stock was $180.16 and there were 8,577,570 OP Units outstanding. Assuming that all of the OP Unit holders exercised their right to redeem all of their OP Units on September 30, 2024 and the Company elected to pay the OP Unit holders cash, the Company would have paid $1,545,335 in cash consideration to redeem the units. OP Unit activity is summarized as follows for the periods presented: For the Nine Months Ended September 30, 2024 2023 OP Units redeemed for common stock 308,024 — OP Units issued in conjunction with business combination and acquisitions — 1,674,748 Value of OP Units issued in conjunction with business combination and acquisitions $ — $ 249,470 GAAP requires a company to present ownership interests in subsidiaries held by parties other than the company in the consolidated financial statements within the equity section, but separate from the company’s equity. It also requires the amount of consolidated net income attributable to the parent and to the noncontrolling interest to be clearly identified and presented on the face of the consolidated statement of operations, and requires changes in ownership interest to be accounted for similarly as equity transactions. If noncontrolling interests are determined to be redeemable, they are to be carried at their redemption value as of the balance sheet date and reported as temporary equity. The Company has evaluated the terms of the OP Units and classifies the noncontrolling interest represented by the OP Units as stockholders’ equity in the accompanying condensed consolidated balance sheets. The Company will periodically evaluate individual noncontrolling interests for the ability to continue to recognize the noncontrolling amount as permanent equity in the condensed consolidated balance sheets. Any noncontrolling interests that fail to qualify as permanent equity will be reclassified as temporary equity and adjusted to the greater of (1) the carrying amount, or (2) its redemption value as of the end of the period in which the determination is made. Other Noncontrolling Interests Other noncontrolling interests represent the ownership interest of partners in nine consolidated joint ventures as of September 30, 2024. There are a total of 13 stores in consolidated joint ventures, seven of which are operating and the other six of which are under development. The voting interests of the partners are 17.0% or less. Based on the facts and circumstances of each of the Company’s joint ventures, the Company has determined that one of the joint ventures at September 30, 2024 was a variable interest entity (“VIE”) in accordance with ASC 810, “Consolidation.” The Company has consolidated that joint venture as it was determined that the Company has the power to direct the activities of the joint venture and is the primary beneficiary of the joint venture.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Segment Information	SEGMENT INFORMATION The Company’s segment disclosures present the measure used by the chief operating decision makers (“CODMs”) for purposes of assessing each segment’s performance. The Company’s CODMs are comprised of several members of its executive management team who use net operating income (“NOI”) to assess the performance of the business for the Company’s reportable operating segments. The Company’s segments are comprised of two reportable segments: (1) self-storage operations and (2) tenant reinsurance. NOI for the Company's self-storage operations represents total property revenue less direct property operating expenses. NOI for the Company's tenant reinsurance segment represents tenant reinsurance revenues less tenant reinsurance expense. The self-storage operations activities include rental operations of wholly-owned stores and self-storage units acquired in the Bargold transaction on June 1, 2022. The Company's consolidated revenues equal total segment revenues plus property management fees and other income. Tenant reinsurance activities include the reinsurance of risks relating to the loss of goods stored by tenants in the stores operated by the Company. Excluded from segment revenues and net operating income is property management fees and other income. For all periods presented, substantially all of the Company's real estate assets, intangible assets, other assets, and accrued and other liabilities are associated with the self-storage operations segment. Financial information for the Company’s business segments is set forth below: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2024 2023 2024 2023 Revenues: Self-Storage Operations $ 710,874 $ 650,887 $ 2,096,018 $ 1,525,596 Tenant Reinsurance 84,048 69,128 249,100 165,265 Total segment revenues $ 794,922 $ 720,015 $ 2,345,118 $ 1,690,861 Operating expenses: Self-Storage Operations $ 209,035 $ 185,194 $ 610,455 $ 416,997 Tenant Reinsurance 17,510 19,130 55,646 37,701 Total segment operating expenses $ 226,545 $ 204,324 $ 666,101 $ 454,698 Net operating income: Self-Storage Operations $ 501,839 $ 465,693 $ 1,485,563 $ 1,108,599 Tenant Reinsurance 66,538 49,998 193,454 127,564 Total segment net operating income: $ 568,377 $ 515,691 $ 1,679,017 $ 1,236,163 Other components of net income: Management fees and other income $ 29,882 $ 28,019 $ 89,888 $ 71,609 Life Storage Merger transition costs — (54,174) — (54,174) General and administrative expense (39,750) (37,406) (123,373) (107,011) Depreciation and amortization expense (195,046) (152,338) (586,821) (309,914) Loss on real estate assets held for sale (8,961) — (63,620) — Interest expense (142,855) (122,899) (412,875) (289,370) Non-cash interest expense related to amortization of discount on Life Storage unsecured senior notes (11,005) (8,228) (32,563) (8,228) Interest income 34,947 22,092 89,746 62,607 Equity in earnings and dividend income from unconsolidated real estate entities 16,246 15,043 48,508 38,602 Equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets 13,730 — 13,730 — Impairment of trade name (51,763) — (51,763) — Income tax expense (10,857) (6,944) (27,443) (17,238) Net income $ 202,945 $ 198,856 $ 622,431 $ 623,046

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES As of September 30, 2024, the Company was under agreement to acquire seven stores at a total purchase price of $74,300. Acquisitions of all seven stores are scheduled to close in 2024. As of September 30, 2024, the Company was involved in various legal proceedings and was subject to various claims and complaints arising in the ordinary course of business. Because litigation is inherently unpredictable, the outcome of these matters cannot presently be determined with any degree of certainty. In accordance with applicable accounting guidance, management establishes an accrued liability for litigation when those matters present loss contingencies that are both probable and reasonably estimable. In such cases, there may be an exposure to loss in excess of any amounts accrued. The estimated loss, if any, is based upon currently available information and is subject to significant judgment, a variety of assumptions, and known and unknown uncertainties. The Company could in the future incur judgments or enter into settlements of claims that could have a material adverse effect on its results of operations in any particular period, notwithstanding the fact that the Company is currently vigorously defending any legal proceedings against it. Although there can be no assurance, the Company is not aware of any material environmental liability, for which it believes it will be ultimately responsible, that could have a material adverse effect on its financial condition or results of operations. However, changes in applicable environmental laws and regulations, the uses and conditions of properties in the vicinity of the Company’s stores, the activities of its tenants and other environmental conditions of which the Company is unaware with respect to its stores could result in future material environmental liabilities.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net income attributable to common stockholders	$ 193,210	$ 188,350	$ 592,194	$ 587,064

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements of the Company are presented on the accrual basis of accounting in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information, and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they may not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the three and nine months ended September 30, 2024 are not necessarily indicative of results that may be expected for the year ending December 31, 2024. The condensed consolidated balance sheet as of December 31, 2023 has been derived from the Company’s audited financial statements as of that date, but does not include all of the information and footnotes required by GAAP for complete financial statements. For further information refer to the consolidated financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the Securities and Exchange Commission.
Recently Issued Accounting Standards	Recently Issued Accounting Standards In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-07 – Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amended guidance requires the disclosure of incremental segment information, including significant segment expenses that are regularly provided to the chief operating decision maker (“CODM”) and a reconciliation of segment profit or loss to net income. The title and position of the CODM must also be disclosed, along with how the CODM uses the reported measures to assess segment performance and to allocate resources. Pursuant to this ASU, the footnotes to the Company's consolidated financial statements may include incremental disclosures related to its two reportable segments: (1) self-storage operations and (2) tenant reinsurance. The compliance with this ASU will be required beginning with the Company's annual report on Form 10-K for the year ending December 31, 2024, followed by interim disclosures in quarterly reports on Form 10-Q thereafter, with early adoption permitted. The Company expects to adopt this ASU for its annual report on Form 10-K for the year ending December 31, 2024.

Fair Value Disclosures (Tables)

Fair Value Disclosures (Tables)	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The table below presents the Company’s assets and liabilities measured at fair value on a recurring basis as of September 30, 2024, aggregated by the level in the fair value hierarchy within which those measurements fall. Fair Value Measurements at Reporting Date Using Description Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other assets - Cash flow hedge swap agreements $ — $ 11,716 $ — Other liabilities - Cash flow hedge swap agreements $ — $ 6,093 $ —
Schedule of Fair Value of Financial Instruments	The fair values of the Company’s fixed-rate liabilities were as follows for the periods indicated: September 30, 2024 December 31, 2023 Fair Carrying Fair Carrying Fixed rate debt $ 8,761,624 $ 9,014,590 $ 7,482,054 $ 8,048,605

Acquisitions and Dispositions (

Acquisitions and Dispositions (Tables)	9 Months Ended
	Sep. 30, 2024
Real Estate [Abstract]
Asset Acquisitions	The following table summarizes the fair value of total consideration transferred in the Life Storage Merger: Consideration Type July 20, 2023 Common stock $ 11,353,338 OP units 249,470 Cash for payoff of Life Storage credit facility and debt 1,192,000 Transaction Costs 55,318 Total consideration $ 12,850,127 The following table summarizes the estimated fair values assigned to the assets acquired and liabilities assumed: July 20, 2023 Real estate assets $ 14,587,735 Equity investment in joint venture partnerships 325,250 Cash and other assets 107,423 Intangible assets - other 82,000 Trade name 50,000 Unsecured senior notes (2,106,866) Accounts payable, accrued expenses and other liabilities (191,077) Noncontrolling interests (4,338) Fair value of net assets acquired $ 12,850,127 Business Combinations (Topic 805): Clarifying the Definition of a Business .” Total Period Number of Stores Cash Paid Loan Assumed Finance Lease Liability Investments in Real Estate Ventures Net Liabilities/ (Assets) Assumed Value of Equity Issued Real estate assets Q3 2024 11 $ 159,196 $ — $ — $ — $ 1,431 $ — $ 160,627 Q2 2024 3 27,644 — — — 97 $ — 27,741 Q1 2024 6 35,084 — — — 171 $ — 35,255 Total 2024 20 $ 221,924 $ — $ — $ — $ 1,699 $ — $ 223,623 Q3 2023 3 $ 18,578 $ — $ — $ — $ 86 $ — $ 18,664 Q2 2023 3 32,888 — — — 26 — 32,914 Q1 2023 1 13,111 — — — 6 — 13,117 Total 2023 7 $ 64,577 $ — $ — $ — $ 118 $ — $ 64,695

Real Estate Assets (Tables)

Real Estate Assets (Tables)	9 Months Ended
	Sep. 30, 2024
Real Estate [Abstract]
Schedule of Components of Real Estate Assets	The components of real estate assets are summarized as follows: September 30, 2024 December 31, 2023 Land $ 4,923,702 $ 4,904,705 Buildings, improvements and other intangibles 22,032,745 21,664,224 Right of use asset - finance lease 143,286 143,842 Intangible assets - tenant relationships 322,771 321,019 Intangible lease rights 27,743 27,743 27,450,247 27,061,533 Less: accumulated depreciation and amortization (3,168,088) (2,624,405) Net operating real estate assets 24,282,159 24,437,128 Real estate under development/redevelopment 103,333 118,745 Real estate assets, net $ 24,385,492 $ 24,555,873 Real estate assets held for sale included in real estate assets, net $ 131,527 $ —

Other Assets (Tables)

Other Assets (Tables)	9 Months Ended
	Sep. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Components of Other Assets	The components of other assets are summarized as follows: September 30, 2024 December 31, 2023 Goodwill $ 170,811 $ 170,811 Receivables, net 112,748 134,716 Prepaid expenses and deposits 97,521 85,153 Other intangible assets, net 39,498 66,332 Trade name — 50,000 Fair value of interest rate swaps 11,716 26,183 Equipment and fixtures, net 50,065 48,697 Deferred line of credit financing costs, net 8,108 9,787 Restricted cash 5,394 6,021 $ 495,861 $ 597,700

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Schedule of Antidilutive Shares Excluded from Computation of Earnings Per Share	The following table presents the number of Common and Preferred Operating Partnership units as if converted into potential common shares that were excluded from the computation of earnings per share as their effect would have been anti-dilutive. For the Three Months Ended September 30, For the Nine Months Ended September 30, 2024 2023 2024 2023 Equivalent Shares (if converted) Equivalent Shares (if converted) Equivalent Shares (if converted) Equivalent Shares (if converted) Common OP Units — 8,541,775 — 7,661,885 Series B Units 198,887 250,061 218,529 228,029 Series D Units 934,585 1,409,198 1,111,927 1,287,256 1,133,472 10,201,034 1,330,456 9,177,170
Schedule of Computation of Earnings Per Common Share	The computation of earnings per common share is as follows for the periods presented: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2024 2023 2024 2023 Net income attributable to common stockholders $ 193,210 $ 188,350 $ 592,194 $ 587,064 Earnings and dividends allocated to participating securities (392) (304) (1,141) (931) Earnings for basic computations 192,818 188,046 591,053 586,133 Income allocated to noncontrolling interest - Preferred Operating Partnership Units and Operating Partnership Units 7,800 — 24,136 — Net income for diluted computations $ 200,618 $ 188,046 $ 615,189 $ 586,133 Weighted average common shares outstanding: Average number of common shares outstanding - basic 211,698,436 195,324,444 211,522,578 155,112,071 OP Units 8,597,656 — 8,651,915 — Shares related to dilutive stock options 2,778 3,576 3,199 4,078 Average number of common shares outstanding - diluted 220,298,870 195,328,020 220,177,692 155,116,149 Earnings per common share Basic $ 0.91 $ 0.96 $ 2.79 $ 3.78 Diluted $ 0.91 $ 0.96 $ 2.79 $ 3.78

Investments in Unconsolidated_2

Investments in Unconsolidated Real Estate Entities (Tables)	9 Months Ended
	Sep. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Schedule of investments in unconsolidated real estate ventures	Net investments in unconsolidated real estate entities and cash distributions in unconsolidated real estate ventures consist of the following: Number of Stores Equity Ownership % Excess Profit % (1) September 30, December 31, 2024 2023 PRISA Self Storage LLC 85 4% 4% $ 9,110 $ 9,435 HF1 Sovran HHF Storage Holdings LLC 37 20% 20% 102,901 105,339 Storage Portfolio II JV LLC 36 10% 30% (9,219) (8,314) Storage Portfolio IV JV LLC 32 10% 30% 47,491 48,184 Storage Portfolio I LLC 24 34% 49% (43,430) (42,487) PR II EXR JV LLC 23 25% 25% 106,456 108,160 HF2 Sovran HHF Storage Holdings II LLC 22 15% 15% 41,039 41,613 HF5 Life Storage-HIERS Storage LLC 17 20% 20% 25,450 26,051 HF6 191 V Life Storage Holdings LLC 17 20% 20% 11,315 12,702 ESS-CA TIVS JV LP 16 55% 55%-65% 27,794 29,128 VRS Self Storage, LLC 16 45% 54% (17,312) (16,386) HF10 Life Storage HHF Wasatch Holdings LLC 16 20% 20% 19,581 20,019 Other unconsolidated real estate ventures (2) (3) 119 10%-50% 10%-50% 314,864 317,104 SmartStop Self Storage REIT, Inc. Preferred Stock (4) n/a n/a n/a 200,000 200,000 Strategic Storage Trust VI, Inc. Preferred Stock (5) n/a n/a n/a 150,000 150,000 Net Investments in and Cash distributions in unconsolidated real estate entities 460 $ 986,040 $ 1,000,548 (1) Includes pro-rata equity ownership share and promoted interest. (2) In August 2024, the ESS Bristol Investments LLC unconsolidated joint venture sold five of its eight stores to another of the Company's unconsolidated joint ventures, and the Company recognized a gain of $10,324 for its pro rata share of the transaction. The Company then acquired its partner's membership interest in the remaining three stores held by ESS Bristol Investments LLC, which is now presented under real estate assets, net on the Company's condensed consolidated balance sheets. (3) In September 2024, the Company sold its membership interest in the Alan Jathoo JV LLC unconsolidated joint venture, which held nine stores, to its partner in such joint venture and recognized a gain of $3,406 on the transaction. This gain and the gain from the ESS Bristol Investments LLC transaction are presented in equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets and sale of a joint venture interest on the Company's condensed consolidated statements of operations for the three months ended September 30, 2024. (4) In October 2019, the Company invested $200,000 in shares of convertible preferred stock of SmartStop with a dividend rate of 6.25% per annum, subject to increase after five years. The preferred shares are generally not redeemable for five years, except in the case of a change of control or initial listing of SmartStop. Dividend income from this investment is included on the equity in earnings and dividend income from unconsolidated real estate entities line on the Company's condensed consolidated statements of operations. (5) In May 2023, the Company invested $150,000 in shares of convertible preferred stock of Strategic Storage with a dividend rate of 8.35% per annum, subject to increase after five years. The preferred shares are generally not redeemable for three years, except in the case of a change of control or initial listing of Strategic Storage. Dividend income from this investment is included on the equity in earnings and dividend income from unconsolidated real estate entities on the Company's condensed consolidated statements of operations.

Investments in Debt Securitie_2

Investments in Debt Securities and Notes Receivable (Tables)	9 Months Ended
	Sep. 30, 2024
Investments, Debt and Equity Securities [Abstract]
Investments in Debt Securities and Bridge Loans Receivable	Information about these balances is as follows: September 30, 2024 December 31, 2023 Debt securities - Preferred Stock $ 300,000 $ 300,000 Notes Receivable - Bridge Loans 1,032,244 594,727 Dividends and Interest Receivable 6,375 10,042 $ 1,338,619 $ 904,769

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2024
Debt Disclosure [Abstract]
Schedule of Unsecured Senior Notes and Components of Debt	The components of term debt are summarized as follows: Term Debt September 30, 2024 December 31, 2023 Secured notes payable (1) $ 1,018,209 $ 1,279,105 Unsecured term loans 2,200,000 2,660,000 Unsecured senior notes 7,725,000 6,725,000 Total 10,943,209 10,664,105 Less: Discount on unsecured senior notes (2) (241,786) (274,350) Less: Unamortized debt issuance costs (57,593) (55,007) Total $ 10,643,830 $ 10,334,748 (1) The loans are collateralized by mortgages on real estate assets and the assignment of rents. (2) Unsecured senior notes from the Life Storage Merger were recorded at fair value, resulting in a discount to be amortized over the term of the debt.
Schedule of Maturities of Notes Payable	The following table summarizes the scheduled maturities of term debt, excluding available extensions, at September 30, 2024: Year Amount 2024 $ — 2025 782,722 2026 1,409,525 2027 1,312,689 2028 1,328,100 2029 1,516,807 2030 1,343,366 2031 1,650,000 2032 600,000 Thereafter 1,000,000 $ 10,943,209
Schedule of Information on Lines of Credit	The following table presents information on the Company’s lines of credit, the proceeds of which are used to repay debt and for general corporate purposes, for the periods indicated: As of September 30, 2024 Revolving Lines of Credit Amount Drawn Capacity Interest Rate Maturity Basis Rate (1) Credit Line 1 (2) $ 55,000 $ 140,000 6.31% 7/1/2026 SOFR plus 1.35% Credit Line 2 (3)(4) 829,000 2,000,000 5.84% 6/22/2027 SOFR plus 0.875% $ 884,000 $ 2,140,000 (1) Daily Simple Secured Overnight Financing Rate (“SOFR”) (2) Secured by mortgages on certain real estate assets. On January 13, 2023, the maturity date was extended to July 1, 2026 with one extension of one (3) Unsecured. On June 22, 2023, the maturity date was extended to June 22, 2027 with two six (4) Basis Rate as of September 30, 2024. Rate is subject to change based on the Company's investment grade rating.

Derivatives (Tables)

Derivatives (Tables)	9 Months Ended
	Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of balance sheet classification and fair value of entity's derivative financial instruments	The table below presents the fair values of the Company’s derivative financial instruments as well as their classification on the condensed consolidated balance sheets: Asset / Liability Derivatives Derivatives designated as hedging instruments: September 30, 2024 December 31, 2023 Other assets $ 11,716 $ 26,183 Other liabilities $ 6,093 $ 5,030
Schedule of information relating to gain (loss) recognized on swap agreements	The table below presents the effect of the Company’s derivative financial instruments on the condensed consolidated statements of operations for the periods presented. No tax effect has been presented as the derivative instruments are held by the Company: Gain (loss) recognized in OCI for the Three Months Ended September 30, Location of amounts reclassified from OCI into income Gain (loss) reclassified from OCI for the Three Months Ended September 30, Type 2024 2023 2024 2023 Swap Agreements $ (17,931) $ 9,146 Interest expense $ 6,965 $ 11,415 Gain (loss) recognized in OCI for the Nine Months Ended September 30, Location of amounts reclassified from OCI into income Gain (loss) reclassified from OCI for the Nine Months Ended September 30, Type 2024 2023 2024 2023 Swap Agreements $ 7,363 $ 27,212 Interest expense $ 22,042 $ 31,398

Noncontrolling Interest Repre_2

Noncontrolling Interest Represented by Preferred Operating Partnership Units (Tables)	9 Months Ended
	Sep. 30, 2024
Noncontrolling Interest [Abstract]
Balances of OP Units	The balances for each of the specific Preferred OP Units as presented in the Statement of Noncontrolling Interests and Equity as of the periods indicated are as follows: September 30, 2024 December 31, 2023 Series B Units $ 33,567 $ 33,567 Series D Units 157,739 188,793 $ 191,306 $ 222,360

Noncontrolling Interest in Op_2

Noncontrolling Interest in Operating Partnership and Other Noncontrolling Interests (Tables)	9 Months Ended
	Sep. 30, 2024
Noncontrolling Interest [Abstract]
Redeemable Noncontrolling Interest	OP Unit activity is summarized as follows for the periods presented: For the Nine Months Ended September 30, 2024 2023 OP Units redeemed for common stock 308,024 — OP Units issued in conjunction with business combination and acquisitions — 1,674,748 Value of OP Units issued in conjunction with business combination and acquisitions $ — $ 249,470

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Schedule of Financial Information of Business Segments	Financial information for the Company’s business segments is set forth below: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2024 2023 2024 2023 Revenues: Self-Storage Operations $ 710,874 $ 650,887 $ 2,096,018 $ 1,525,596 Tenant Reinsurance 84,048 69,128 249,100 165,265 Total segment revenues $ 794,922 $ 720,015 $ 2,345,118 $ 1,690,861 Operating expenses: Self-Storage Operations $ 209,035 $ 185,194 $ 610,455 $ 416,997 Tenant Reinsurance 17,510 19,130 55,646 37,701 Total segment operating expenses $ 226,545 $ 204,324 $ 666,101 $ 454,698 Net operating income: Self-Storage Operations $ 501,839 $ 465,693 $ 1,485,563 $ 1,108,599 Tenant Reinsurance 66,538 49,998 193,454 127,564 Total segment net operating income: $ 568,377 $ 515,691 $ 1,679,017 $ 1,236,163 Other components of net income: Management fees and other income $ 29,882 $ 28,019 $ 89,888 $ 71,609 Life Storage Merger transition costs — (54,174) — (54,174) General and administrative expense (39,750) (37,406) (123,373) (107,011) Depreciation and amortization expense (195,046) (152,338) (586,821) (309,914) Loss on real estate assets held for sale (8,961) — (63,620) — Interest expense (142,855) (122,899) (412,875) (289,370) Non-cash interest expense related to amortization of discount on Life Storage unsecured senior notes (11,005) (8,228) (32,563) (8,228) Interest income 34,947 22,092 89,746 62,607 Equity in earnings and dividend income from unconsolidated real estate entities 16,246 15,043 48,508 38,602 Equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets 13,730 — 13,730 — Impairment of trade name (51,763) — (51,763) — Income tax expense (10,857) (6,944) (27,443) (17,238) Net income $ 202,945 $ 198,856 $ 622,431 $ 623,046

Organization (Detail)

Organization (Detail)	Sep. 30, 2024 state store
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating storage facilities in which the entity has equity interests (in stores)	2,401
Number of stores owned by franchisees and third parties	1,461
Number of operating stores owned and/or managed	3,862
Number of states in which operating storage facilities are located | state	42

Basis of Presentation (Details)

Basis of Presentation (Details)	9 Months Ended
	Sep. 30, 2024 segment
Accounting Policies [Abstract]
Number of reportable segments	2

Fair Value Disclosures - Assets

Fair Value Disclosures - Assets and Liabilities on a Recurring Basis (Detail) - Recurring Basis $ in Thousands	Sep. 30, 2024 USD ($)
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	$ 0
Other liabilities	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	11,716
Other liabilities	6,093
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0
Other liabilities	$ 0

Fair Value Disclosures - Schedu

Fair Value Disclosures - Schedule of Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value
Fair Value of Financial Instruments [Line Items]
Fixed rate debt	$ 8,761,624	$ 7,482,054
Carrying Value
Fair Value of Financial Instruments [Line Items]
Fixed rate debt	$ 9,014,590	$ 8,048,605

Fair Value Disclosures - Additi

Fair Value Disclosures - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) store	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) store	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Fair Value of Financial Instruments [Line Items]
Number of operating stores held-for-sale | store	17		17
Real estate assets held for sale included in real estate assets, net	$ 131,527		$ 131,527		$ 0
Loss on real estate assets held for sale	(8,961)	$ 0	(63,620)	$ 0
Nine Stores
Fair Value of Financial Instruments [Line Items]
Real estate assets held for sale included in real estate assets, net	$ 70,952		70,952
Loss on real estate assets held for sale			$ (63,620)

Acquisitions and Dispositions -

Acquisitions and Dispositions - Additional Information (Details) $ in Thousands			9 Months Ended
	Jul. 25, 2023 USD ($)	Jul. 20, 2023 USD ($) joint_venture store shares	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Asset Acquisition [Line Items]
Total consideration paid for repurchase			$ 6,062,896	$ 4,617,755
Life Storage, Inc
Asset Acquisition [Line Items]
Total consideration paid for repurchase		$ 375,000
Unsecured senior notes
Asset Acquisition [Line Items]
Senior note balances			$ 7,725,000		$ 6,725,000
Unsecured senior notes | Senior Notes, Assumed From Life Storage
Asset Acquisition [Line Items]
Total consideration paid for repurchase	$ 2,351,100
Senior note balances	$ 48,900
Life Storage, Inc
Asset Acquisition [Line Items]
Wholly-owned stores acquired | store		757
Joint venture stores acquired | joint_venture		1
Equity interest issued conversion ratio (in shares) | shares		0.895
Consideration transferred		$ 11,602,808
Real estate assets, estimated useful life		39 years
Tenant relationships, estimated useful life		18 months
Intangible assets, amortization period		36 months
Life Storage, Inc | Line of Credit
Asset Acquisition [Line Items]
Extinguishment of liability component		$ 1,160,000
Life Storage, Inc | Secured Debt
Asset Acquisition [Line Items]
Total consideration paid for repurchase		$ 32,000

Acquisitions and Dispositions_2

Acquisitions and Dispositions - Asset Acquisition - Life Storage (Details) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended
	Jul. 20, 2023	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Asset Acquisition [Line Items]
Total consideration		$ 160,627	$ 27,741	$ 35,255	$ 18,664	$ 32,914	$ 13,117	$ 223,623	$ 64,695
Life Storage, Inc
Asset Acquisition [Line Items]
Equity	$ 11,602,808
Cash for payoff of Life Storage credit facility and debt	1,192,000
Transaction Costs	55,318
Total consideration	12,850,127
Real estate assets	14,587,735
Equity investment in joint venture partnerships	325,250
Cash and other assets	107,423
Intangible assets - other	82,000
Trade name	50,000
Unsecured senior notes	(2,106,866)
Accounts payable, accrued expenses and other liabilities	(191,077)
Noncontrolling interests	(4,338)
Fair value of net assets acquired	12,850,127
Life Storage, Inc | Common stock
Asset Acquisition [Line Items]
Equity	11,353,338
Life Storage, Inc | OP units
Asset Acquisition [Line Items]
Equity	$ 249,470

Acquisitions and Dispositions_3

Acquisitions and Dispositions - Asset Acquisitions - Schedule of Operating Properties Acquired (Details) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024 USD ($) store	Jun. 30, 2024 USD ($) store	Mar. 31, 2024 USD ($) store	Sep. 30, 2023 USD ($) store	Jun. 30, 2023 USD ($) store	Mar. 31, 2023 USD ($) store	Sep. 30, 2024 USD ($) store	Sep. 30, 2023 USD ($) store
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Number of Stores | store	11	3	6	3	3	1	20	7
Cash Paid	$ 159,196	$ 27,644	$ 35,084	$ 18,578	$ 32,888	$ 13,111	$ 221,924	$ 64,577
Loan Assumed	0	0	0	0	0	0	0	0
Finance Lease Liability	0	0	0	0	0	0	0	0
Investment in unconsolidated real estate ventures	0	0	0	0	0	0	0	0
Net Liabilities/ (Assets) Assumed	1,431	97	171	86	26	6	1,699	118
Value of units issued	0	0	0	0	0	0	0	0
Total	$ 160,627	$ 27,741	$ 35,255	$ 18,664	$ 32,914	$ 13,117	$ 223,623	$ 64,695

Real Estate Assets - Schedule o

Real Estate Assets - Schedule of Components of Real Estate Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Real Estate [Abstract]
Land	$ 4,923,702	$ 4,904,705
Buildings, improvements and other intangibles	22,032,745	21,664,224
Right of use asset - finance lease	143,286	143,842
Intangible assets - tenant relationships	322,771	321,019
Intangible lease rights	27,743	27,743
Gross operating real estate assets	27,450,247	27,061,533
Less: accumulated depreciation and amortization	(3,168,088)	(2,624,405)
Net operating real estate assets	24,282,159	24,437,128
Real estate under development/redevelopment	103,333	118,745
Real estate assets, net	24,385,492	24,555,873
Real estate assets held for sale included in real estate assets, net	$ 131,527	$ 0

Real Estate Assets - Additional

Real Estate Assets - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2024 store	Sep. 30, 2024 USD ($) store	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) store	Sep. 30, 2023 USD ($)
Real Estate [Abstract]
Number of stores with amended leases	27
Number of stores with new triple-net lease agreement	12
Number of operating stores held-for-sale	17	17		17
Loss on real estate assets held for sale | $		$ (8,961)	$ 0	$ (63,620)	$ 0

Other Assets (Details)

Other Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Goodwill	$ 170,811		$ 170,811		$ 170,811
Receivables, net	112,748		112,748		134,716
Prepaid expenses and deposits	97,521		97,521		85,153
Other intangible assets, net	39,498		39,498		66,332
Trade name	0		0		50,000
Fair value of interest rate swaps	11,716		11,716		26,183
Equipment and fixtures, net	50,065		50,065		48,697
Deferred line of credit financing costs, net	8,108		8,108		9,787
Restricted cash	5,394	$ 7,000	5,394	$ 7,000	6,021	$ 4,867
Other assets, net	495,861		495,861		$ 597,700
Impairment of Life Storage trade name	$ (51,763)	$ 0	$ (51,763)	$ 0

Earnings Per Common Share - Add

Earnings Per Common Share - Additional Information (Detail) - $ / shares	3 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Average share price (in dollars per share)	$ 168.78	$ 134.24

Earnings Per Common Share - Ant

Earnings Per Common Share - Antidilutive Shares (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per common share (in shares)	1,133,472	10,201,034	1,330,456	9,177,170
Common OP Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per common share (in shares)	0	8,541,775	0	7,661,885
Series B Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per common share (in shares)	198,887	250,061	218,529	228,029
Series D Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per common share (in shares)	934,585	1,409,198	1,111,927	1,287,256

Earnings Per Common Share - Sch

Earnings Per Common Share - Schedule of Computation (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net income attributable to common stockholders	$ 193,210	$ 188,350	$ 592,194	$ 587,064
Earnings and dividends allocated to participating securities	(392)	(304)	(1,141)	(931)
Earnings for basic computations	192,818	188,046	591,053	586,133
Income allocated to noncontrolling interest - Preferred Operating Partnership Units and Operating Partnership Units	7,800	0	24,136	0
Net income for diluted computations	$ 200,618	$ 188,046	$ 615,189	$ 586,133
Weighted average common shares outstanding:
Average number of common shares outstanding - basic	211,698,436	195,324,444	211,522,578	155,112,071
OP Units (in shares)	8,597,656	0	8,651,915	0
Shares related to exchangeable senior notes and dilutive stock options (in shares)	2,778	3,576	3,199	4,078
Average number of common shares outstanding - diluted (in shares)	220,298,870	195,328,020	220,177,692	155,116,149
Earnings per common share
Basic (in dollars per share)	$ 0.91	$ 0.96	$ 2.79	$ 3.78
Diluted (in dollars per share)	$ 0.91	$ 0.96	$ 2.79	$ 3.78

Investments in Unconsolidated_3

Investments in Unconsolidated Real Estate Entities (Details) $ in Thousands	1 Months Ended
	Sep. 30, 2024 USD ($) property joint_venture	Aug. 31, 2024 USD ($) store	May 31, 2023 USD ($)	Oct. 31, 2019 USD ($)	Dec. 31, 2023 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	460
Investment balance	$ 986,040				$ 1,000,548
ESS Bristol Investments LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | store		8
Number of stores sold | store		5
Gain on sale of joint ventures		$ 10,324
PRISA Self Storage LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	85
Equity Ownership %	4%
Excess Profit %	4%
Investment balance	$ 9,110				9,435
HF1 Sovran HHF Storage Holdings LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	37
Equity Ownership %	20%
Excess Profit %	20%
Investment balance	$ 102,901				105,339
Storage Portfolio II JV LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	36
Equity Ownership %	10%
Excess Profit %	30%
Investment balance	$ (9,219)				(8,314)
Storage Portfolio IV JV LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	32
Equity Ownership %	10%
Excess Profit %	30%
Investment balance	$ 47,491				48,184
Storage Portfolio I LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	24
Equity Ownership %	34%
Excess Profit %	49%
Investment balance	$ (43,430)				(42,487)
PR II EXR JV LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	23
Equity Ownership %	25%
Excess Profit %	25%
Investment balance	$ 106,456				108,160
HF2 Sovran HHF Storage Holdings II LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	22
Equity Ownership %	15%
Excess Profit %	15%
Investment balance	$ 41,039				41,613
HF5 Life Storage-HIERS Storage LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	17
Equity Ownership %	20%
Excess Profit %	20%
Investment balance	$ 25,450				26,051
HF6 191 V Life Storage Holdings LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	17
Equity Ownership %	20%
Excess Profit %	20%
Investment balance	$ 11,315				12,702
ESS-CA TIVS JV LP
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	16
Equity Ownership %	55%
Investment balance	$ 27,794				29,128
ESS-CA TIVS JV LP | Minimum
Schedule of Equity Method Investments [Line Items]
Excess Profit %	55%
ESS-CA TIVS JV LP | Maximum
Schedule of Equity Method Investments [Line Items]
Excess Profit %	65%
VRS Self Storage, LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	16
Equity Ownership %	45%
Excess Profit %	54%
Investment balance	$ (17,312)				(16,386)
HF10 Life Storage HHF Wasatch Holdings LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	16
Equity Ownership %	20%
Excess Profit %	20%
Investment balance	$ 19,581				20,019
Other unconsolidated real estate ventures (2) (3)
Schedule of Equity Method Investments [Line Items]
Number of Stores | property	119
Investment balance	$ 314,864				317,104
Other unconsolidated real estate ventures (2) (3) | Minimum
Schedule of Equity Method Investments [Line Items]
Equity Ownership %	10%
Other unconsolidated real estate ventures (2) (3) | Maximum
Schedule of Equity Method Investments [Line Items]
Equity Ownership %	50%
SmartStop Self Storage REIT, Inc. Preferred Stock
Schedule of Equity Method Investments [Line Items]
Investment balance	$ 200,000			$ 200,000	200,000
Investment, preferred dividend rate				6.25%
Period after which preferred stock dividend is subject to increase				5 years
Investment redemption restriction period				5 years
Strategic Storage Trust VI, Inc. Preferred Stock
Schedule of Equity Method Investments [Line Items]
Investment balance	$ 150,000				$ 150,000
Investment in shares			$ 150,000
Dividend rate, percentage			8.35%
Dividend rate increase, threshold			5 years
Redemption period			3 years
Alan Jathoo JV LLC
Schedule of Equity Method Investments [Line Items]
Number of stores sold | joint_venture	9
Gain on sale of joint ventures	$ 3,406
ESS Bristol Investments LLC
Schedule of Equity Method Investments [Line Items]
Number of stores purchased | store		3

Investments in Debt Securitie_3

Investments in Debt Securities and Notes Receivable - Schedule (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Schedule of Held-to-maturity Securities [Line Items]
Dividends and Interest Receivable	$ 6,375	$ 10,042
Investments in debt securities and notes receivable	1,338,619	904,769
Notes Receivable-Bridge Loans
Schedule of Held-to-maturity Securities [Line Items]
Notes Receivable - Bridge Loans	1,032,244	594,727
JCAP Series A Preferred Stock
Schedule of Held-to-maturity Securities [Line Items]
Debt securities - Preferred Stock	$ 300,000	$ 300,000

Investments in Debt Securitie_4

Investments in Debt Securities and Notes Receivable - Additional Information (Details) $ in Thousands	1 Months Ended		3 Months Ended	9 Months Ended
	Dec. 31, 2022 USD ($) shares	Nov. 30, 2020 USD ($) extension_option shares	Sep. 30, 2024 debt_security extension_option Rate	Sep. 30, 2024 USD ($) extension_option Rate	Sep. 30, 2023 USD ($)
Schedule of Held-to-maturity Securities [Line Items]
Investment in debt securities		$ 300,000
Debt securities, term		6 years
Debt securities, extension option | extension_option		2
Debt securities, extension term		1 year
Debt securities, period after which preferred dividends increase annually		6 years
Bridge loans, percent of notes held as mortgage receivables | Rate			71%	71%
Bridge loans, extension option | extension_option			2	2
Bridge loans, extension term				1 year
Proceeds from sale of notes receivable				$ 175,335	$ 134,064
Issuance and purchase of notes receivable				$ 739,702	$ 210,712
Number of debt securities past due or nonaccrual status | debt_security			1
Minimum
Schedule of Held-to-maturity Securities [Line Items]
Loan to value ratio				0.70
Maximum
Schedule of Held-to-maturity Securities [Line Items]
Loan to value ratio				0.80
Notes Receivable-Bridge Loans
Schedule of Held-to-maturity Securities [Line Items]
Bridge loans, original maturities				3 years
Principal amount of notes sold				$ 175,335
Proceeds from sale of notes receivable				175,335
Issuance and purchase of notes receivable				636,215
Payment of draws from interest holdbacks				$ 39,709
JCAP Series A Preferred Stock
Schedule of Held-to-maturity Securities [Line Items]
Investment in debt securities		$ 200,000
Investment in debt securities (in shares) | shares		200,000
Debt securities, dividend rate		8.50%
JCAP Series B Preferred Stock
Schedule of Held-to-maturity Securities [Line Items]
Investment in debt securities		$ 100,000
Investment in debt securities (in shares) | shares		100,000
JCAP Series D Preferred Stock
Schedule of Held-to-maturity Securities [Line Items]
Shares exchanged (in shares) | shares	300,000
Shares exchanged, value	$ 300,000

Debt - Schedule of Components o

Debt - Schedule of Components of Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Notes Payable
Debt Instrument [Line Items]
Term debt	$ 1,018,209	$ 1,279,105
Less: Unamortized debt issuance costs	(57,593)	(55,007)
Unsecured Term Loans
Debt Instrument [Line Items]
Term debt	2,200,000	2,660,000
Unsecured senior notes
Debt Instrument [Line Items]
Term debt	7,725,000	6,725,000
Discount on unsecured senior notes	(241,786)	(274,350)
Term Debt
Debt Instrument [Line Items]
Term debt	10,943,209	10,664,105
Total	$ 10,643,830	$ 10,334,748

Debt - Schedule of Maturities o

Debt - Schedule of Maturities of Notes Payable (Details) - Term Debt - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
2024	$ 0
2025	782,722
2026	1,409,525
2027	1,312,689
2028	1,328,100
2029	1,516,807
2030	1,343,366
2031	1,650,000
2032	600,000
Thereafter	1,000,000
Total	$ 10,943,209	$ 10,664,105

Debt - Additional Information (

Debt - Additional Information (Details)		9 Months Ended
	Jan. 13, 2023 Year	Sep. 30, 2024 USD ($) extension_option
Debt Instrument [Line Items]
Fixed rate to total debt percentage		78.30%
Fixed rate debt		4%
Variable rate debt		6%
Weighted average interest rate		4.50%
Credit Line 1
Debt Instrument [Line Items]
Capacity | $		$ 140,000,000
Number of extensions available | Year	1
Extension term	1 year
Basis spread on variable rate		1.35%
Line of Credit
Debt Instrument [Line Items]
Number of extensions available | extension_option		2
Extension term		6 months
Line of Credit | Base rate
Debt Instrument [Line Items]
Basis spread on variable rate		0%
Line of Credit | Base rate | Investment grade election | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		0%
Line of Credit | Base rate | Investment grade election | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		1.20%
Line of Credit | Federal funds rate
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Line of Credit | SOFR
Debt Instrument [Line Items]
Basis spread on variable rate		1%
Line of Credit | SOFR | Investment grade election | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		0.70%
Line of Credit | SOFR | Investment grade election | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		2.20%

Debt - Schedule of Information

Debt - Schedule of Information on Lines of Credit (Details)			9 Months Ended
	Jun. 22, 2023 extension_option	Jan. 13, 2023 Year	Sep. 30, 2024 USD ($) extension_option	Dec. 31, 2023 USD ($)	Aug. 11, 2023 USD ($)
Debt Instrument [Line Items]
Amount Drawn			$ 884,000,000	$ 682,000,000
Line of Credit
Debt Instrument [Line Items]
Number of extensions available | extension_option			2
Extension term			6 months
Credit Line 1
Debt Instrument [Line Items]
Amount Drawn			$ 55,000,000
Capacity			$ 140,000,000
Interest Rate			6.31%
Basis spread on variable rate			1.35%
Number of extensions available | Year		1
Extension term		1 year
Credit Line 2
Debt Instrument [Line Items]
Amount Drawn			$ 829,000,000
Capacity			$ 2,000,000,000		$ 60,000,000
Interest Rate			5.84%
Basis spread on variable rate			0.875%
Number of extensions available | extension_option	2
Extension term	6 months
Lines Of Credit
Debt Instrument [Line Items]
Amount Drawn			$ 884,000,000
Capacity			$ 2,140,000,000

Derivatives - Additional Inform

Derivatives - Additional Information (Detail) $ in Thousands	Sep. 30, 2024 USD ($) derivative
Derivative [Line Items]
Amount reclassified as an increase to interest income	$ (7,681)
Number of derivative financial instruments | derivative	14
Combined notional amount	$ 1,382,568
Derivatives with contingent features, net liability position	5,423
Derivative, termination value	$ 5,423
Interest Rate Swap, Forward-Starting
Derivative [Line Items]
Number of derivative financial instruments | derivative	2

Derivatives - Schedule of Balan

Derivatives - Schedule of Balance Sheet Classification and Fair Value of Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Other assets
Derivative [Line Items]
Other assets	$ 11,716	$ 26,183
Other liabilities
Derivative [Line Items]
Other liabilities	$ 6,093	$ 5,030

Derivatives - Gain (Loss) Recog

Derivatives - Gain (Loss) Recognized on Swap Agreements (Detail) - Swap Agreements - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Derivative [Line Items]
Gain (loss) recognized in OCI	$ (17,931)	$ 9,146	$ 7,363	$ 27,212
Gain (loss) reclassified from OCI	$ 6,965	$ 11,415	$ 22,042	$ 31,398

Stockholders' Equity (Detail)

Stockholders' Equity (Detail) $ / shares in Units, $ in Thousands			9 Months Ended	12 Months Ended	32 Months Ended
	Apr. 15, 2024 USD ($) sales_agent shares	Jul. 20, 2023 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) shares	Dec. 31, 2023 shares	Apr. 14, 2024 shares	Nov. 13, 2023 USD ($)
Class of Stock [Line Items]
Share repurchase program, authorized amount						$ 500,000
Repurchase of common stock (in shares) | shares			0	0
Share repurchase program, remaining authorization			$ 500,000
Issuance of common stock in conjunction with acquisitions (in shares) | shares		76,217,359
Price per share (dollars per share) | $ / shares		$ 148.96
Issuance of common stock in conjunction with acquisitions, value		$ 11,353,338
At the Market Equity Distribution Agreement
Class of Stock [Line Items]
Aggregate offering price of common shares	$ 800,000
Number of sales agents | sales_agent	9
Shares issued (in shares) | shares	0				0

Noncontrolling Interest Repre_3

Noncontrolling Interest Represented by Preferred Operating Partnership Units - Balances of OP Units (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Noncontrolling Interest [Line Items]
Noncontrolling interest represented by Preferred Operating Partnership units, net	$ 191,306	$ 222,360
Series B Units
Noncontrolling Interest [Line Items]
Noncontrolling interest represented by Preferred Operating Partnership units, net	33,567	33,567
Series D Units
Noncontrolling Interest [Line Items]
Noncontrolling interest represented by Preferred Operating Partnership units, net	$ 157,739	$ 188,793

Noncontrolling Interest Repre_4

Noncontrolling Interest Represented by Preferred Operating Partnership Units - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Noncontrolling Interest [Line Items]
Preferred units outstanding (in shares)	8,577,570
Series B Units
Noncontrolling Interest [Line Items]
Preferred units outstanding (in shares)	1,342,727
Liquidation value (in dollars per share)	$ 25
Fixed liquidation value	$ 33,567
Annual rate of return percentage	6%
Series D Units
Noncontrolling Interest [Line Items]
Liquidation value (in dollars per share)	$ 25
Fixed liquidation value	$ 157,739
Fixed liquidation value (in shares)	6,309,567
Redemption of Operating Partnership units (in shares)	1,242,168
Redemption of operating partnership units for common stock (in shares)	213,661
Series D Units | Minimum
Noncontrolling Interest [Line Items]
Annual rate of return percentage	3%
Series D Units | Maximum
Noncontrolling Interest [Line Items]
Annual rate of return percentage	5%
Series A Units
Noncontrolling Interest [Line Items]
Preferred units outstanding (in shares)	0	0
Series C Units
Noncontrolling Interest [Line Items]
Preferred units outstanding (in shares)	0	0

Noncontrolling Interest in Op_3

Noncontrolling Interest in Operating Partnership and Other Noncontrolling Interests - Additional Information (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($) joint_venture store $ / shares shares	Dec. 31, 2023 USD ($)
Noncontrolling Interest [Line Items]
Note receivable interest rate	5%
Period used as a denomination to determine the average closing price of common stock	10 days
Ten day average closing stock price (in dollars per share) | $ / shares	$ 180.16
Preferred units outstanding (in shares) | shares	8,577,570
Consideration to be paid on redemption of common OP units | $	$ 1,545,335
Number of consolidated joint ventures | joint_venture	9
Total number of stores in consolidated joint venture | store	13
Number of joint ventures operating store | joint_venture	7
Number of joint ventures with property under development | store	6
Operating Partnership
Noncontrolling Interest [Line Items]
Loan receivable, reduction of noncontrolling interests | $	$ 1,900	$ 1,900
Common stock
Noncontrolling Interest [Line Items]
OP units conversion ratio	1
Operating Partnership
Noncontrolling Interest [Line Items]
Ownership interest held	95.60%
Ownership interest held by joint venture partner	4.40%
Other noncontrolling interests | Maximum
Noncontrolling Interest [Line Items]
Ownership interest held by joint venture partner	17%

Noncontrolling Interest in Op_4

Noncontrolling Interest in Operating Partnership and Other Noncontrolling Interests - Schedule of OP Unit Activity (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Jul. 20, 2023
Noncontrolling Interest [Abstract]
OP Units redeemed for common stock (in shares)	308,024	0
OP Units issued in conjunction with business combination acquisitions (in units)		1,674,748	0
Value of OP Units issued in conjunction with business combination and acquisitions		$ 249,470	$ 0

Segment Information - Additiona

Segment Information - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2024 segment
Segment Reporting [Abstract]
Number of reportable segments	2

Segment Information - Schedule

Segment Information - Schedule of Financial Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Revenues:	$ 824,804	$ 748,034	$ 2,435,006	$ 1,762,470
Operating expenses:	461,341	448,242	1,376,295	925,797
Net operating income:	302,739	299,792	943,328	836,673
Management fees and other income	29,882	28,019	89,888	71,609
Life Storage Merger transition costs	0	54,174	0	54,174
General and administrative expense	(39,750)	(37,406)	(123,373)	(107,011)
Depreciation and amortization expense	(195,046)	(152,338)	(586,821)	(309,914)
Loss on real estate assets held for sale	(8,961)	0	(63,620)	0
Interest expense	(142,855)	(122,899)	(412,875)	(289,370)
Non-cash interest expense related to amortization of discount on Life Storage unsecured senior notes	(11,005)	(8,228)	(32,563)	(8,228)
Interest income	34,947	22,092	89,746	62,607
Equity in earnings and dividend income from unconsolidated real estate entities	16,246	15,043	48,508	38,602
Equity in earnings of unconsolidated real estate ventures - gain on sale of real estate assets and sale of a joint venture interest	13,730	0	13,730	0
Impairment of trade name	(51,763)	0	(51,763)	0
Income tax expense	(10,857)	(6,944)	(27,443)	(17,238)
Operating Segments
Segment Reporting Information [Line Items]
Revenues:	794,922	720,015	2,345,118	1,690,861
Operating expenses:	226,545	204,324	666,101	454,698
Net operating income:	568,377	515,691	1,679,017	1,236,163
Self-Storage Operations | Operating Segments
Segment Reporting Information [Line Items]
Revenues:	710,874	650,887	2,096,018	1,525,596
Operating expenses:	209,035	185,194	610,455	416,997
Net operating income:	501,839	465,693	1,485,563	1,108,599
Tenant Reinsurance | Operating Segments
Segment Reporting Information [Line Items]
Revenues:	84,048	69,128	249,100	165,265
Operating expenses:	17,510	19,130	55,646	37,701
Net operating income:	$ 66,538	$ 49,998	$ 193,454	$ 127,564

Commitments and Contingencies (

Commitments and Contingencies (Detail) $ in Thousands	Sep. 30, 2024 USD ($) store
Commitment to acquire stores
Other Commitments [Line Items]
Number of real estate properties to be acquired	7
Purchase price | $	$ 74,300
Commitment to acquire stores, scheduled to close in current fiscal year
Other Commitments [Line Items]
Number of real estate properties to be acquired	7