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Investment in Storage Facilities and Intangible Assets - Additional Information (Detail) $ / shares in Units, $ in Thousands		1 Months Ended				12 Months Ended
	Apr. 01, 2021 USD ($)	Aug. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2021 USD ($) Property	Sep. 30, 2020 USD ($) Property	Dec. 31, 2022 USD ($) Property	Dec. 31, 2021 USD ($) Property $ / shares	Dec. 31, 2020 USD ($) Property $ / shares	Apr. 30, 2022 USD ($)
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property						50	112	40
Cash payment for property acquisition						$ 953,464	$ 1,514,713
Distributions from unconsolidated joint ventures						$ 17,628	$ 13,866	$ 14,098
Number of facilities acquired \| Property						9	27
Minority interest ownership percentage		17.00%
Noncontrolling interest in consolidated subsidiary						$ 4,917	$ 0
Fair value of mortgage assumed								6,400
Net other liabilities assumed						4,200	(8,900)	1,800
Issuance of Operating Partnership Units						$ 15,215	172,716
Amortization period for in-place customer leases on a straight-line basis						12 months
Amortization expense related to in-place customer leases						$ 20,200	12,400	5,600
Amortization expense to be expected for 2023						4,200
Number of storage facilities sold \| Property					4
Increase in depreciation expense due to facility replacement						$ 200	$ 2,500	$ 5,800
Accelerated depreciation reduced basic and diluted earnings per share \| $ / shares							$ 0.03	$ 0.08
Non-strategic Properties [Member]
Investment Holdings [Line Items]
Number of storage facilities sold \| Property						0	0	0
Common Stock [Member]
Investment Holdings [Line Items]
Issuance of Operating Partnership Units							$ 82,900
Preferred Stock [Member]
Investment Holdings [Line Items]
Issuance of Operating Partnership Units							89,800
Life Storage-HIERS Storage LLC [Member]
Investment Holdings [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership						20.00%
Carrying value of investment						$ 13,700	$ 13,900
SNL Orix Merrick, LLC, Merrick [Member]
Investment Holdings [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership						5.00%	5.00%
Cash payment for property acquisition						$ 47,900
Distributions from unconsolidated joint ventures						800
Total consideration acquired							$ 47,900
Life Storage S E R S Storage L L C [Member]
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property				3
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership				20.00%
Cash payment for property acquisition						51,700
Distributions from unconsolidated joint ventures				$ 2,800		$ 8,300
Sovran HHF Storage Holdings LLC [Member]
Investment Holdings [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership						20.00%
Carrying value of investment						$ 63,600	58,700
Total consideration acquired			$ 33,400		$ 175,200
Sovran HHF Storage Holdings II LLC [Member]
Investment Holdings [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership						15.00%
Distributions from unconsolidated joint ventures	$ 31,600
Carrying value of investment						$ (2,400)	$ (2,400)
Total consideration acquired					$ 120,200
Life Storage898 Mcdonald Llc [Member]
Investment Holdings [Line Items]
Issuance of Operating Partnership Units						10,300
NY [Member]
Investment Holdings [Line Items]
Carrying value of investment						$ 24,100
Total consideration acquired		$ 29,000
Retained interest in joint venture		$ 4,900
Ownership percentage in joint venture		83.00%
NY [Member] \| Life Storage898 Mcdonald Llc [Member]
Investment Holdings [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership									14.20%
Carrying value of investment									$ 30,200
Third Parties [Member]
Investment Holdings [Line Items]
Number of facilities acquired \| Property						39	81