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Investment in Joint Ventures - Summary of Company's Unconsolidated Joint Ventures (Parenthetical) (Detail) $ in Thousands			1 Months Ended											3 Months Ended	9 Months Ended
	Sep. 30, 2022 USD ($) Property	Apr. 01, 2021 USD ($)	Oct. 31, 2022 USD ($)	Sep. 30, 2022 USD ($) Property	Aug. 31, 2022 USD ($)	Jul. 31, 2022 USD ($) Property	Jun. 30, 2022 USD ($)	Apr. 30, 2022 USD ($)	Dec. 31, 2021 USD ($) Property	Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($) Property	Sep. 30, 2020 USD ($) Property	Sep. 30, 2022 USD ($) Property	Sep. 30, 2022 USD ($) Property	Sep. 30, 2021 USD ($) Property	Apr. 30, 2021 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired \| Property															43	62
Contribution of company to joint venture as share in capital														$ 1,200
Distributions from unconsolidated joint ventures															$ 12,710	$ 10,359
Rent paid during the period															1,200	$ 1,100
Mortgages payable	$ 36,454			$ 36,454					$ 37,030					36,454	36,454
Purchase price of business to be acquired				59,000
NY [Member]
Schedule of Equity Method Investments [Line Items]
Total consideration acquired					$ 29,000
Storage Facilities [Member]
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired \| Property									13			17
Total consideration acquired									$ 290,600			$ 320,000
Contribution of company to joint venture as share in capital									$ 52,000			$ 28,700
Mortgage debt maturity year									2029			2026
Mortgages payable									$ 145,300			$ 184,000
Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Excess of investment over net asset due to capitalization of acquisition related costs	$ 1,700			$ 1,700										$ 1,700	$ 1,700
Total consideration acquired							$ 31,700
Additional contribution							$ 6,700
Company common ownership interest	20.00%			20.00%										20.00%	20.00%
Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Total consideration acquired													$ 120,200
Cash has been placed into escrow until non-recourse loans																	$ 35,800
Contribution of company to joint venture as share in capital													$ 12,700
Company common ownership interest	15.00%			15.00%										15.00%	15.00%
Mortgage debt paid off		$ 69,100
Mortgage debt maturity year		2029
Distributions from unconsolidated joint ventures		$ 31,600
Mortgages payable		$ 110,000
Sovran HHF Storage Holdings II LLC [Member] \| Storage Facilities [Member]
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired \| Property													8
Life Storage ArrowMark Venture LLC [Member]
Schedule of Equity Method Investments [Line Items]
Total consideration acquired			$ 2,800							$ 1,600
Company common ownership interest	50.00%			50.00%										50.00%	50.00%
SNL Orix 1200 McDonald Ave., LLC [Member]
Schedule of Equity Method Investments [Line Items]
Excess of investment over net asset due to capitalization of acquisition related costs								$ 30,200
Contribution of company to joint venture as share in capital											$ 27,300
Asset Acquisition, Consideration Transferred								$ 5,200
SNL Orix 1200 McDonald Ave., LLC [Member] \| Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Company common ownership interest											5.00%					5.00%
SNL Orix 1200 McDonald Ave., LLC [Member] \| Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Company common ownership interest											86.00%					86.00%
Joint Ventures with Properties in Development Stage [Member]
Schedule of Equity Method Investments [Line Items]
Number Of joint ventures \| Property															6
Joint Ventures with Properties in Development Stage [Member] \| Ontario, Canada [Member]
Schedule of Equity Method Investments [Line Items]
Number of joint venture developing self-storage facilities \| Property	1			1										1	1
Joint Ventures with Properties in Development Stage [Member] \| NY [Member]
Schedule of Equity Method Investments [Line Items]
Number of joint venture developing self-storage facilities \| Property	4			4										4	4
Joint Ventures with Properties in Development Stage [Member] \| Tampa, FL [Member]
Schedule of Equity Method Investments [Line Items]
Number of joint venture developing self-storage facilities \| Property	1			1										1	1
Joint Ventures with Properties in Development Stage [Member] \| Common Stock Shares [Member]
Schedule of Equity Method Investments [Line Items]
Total consideration acquired															$ 18,800
Life Storage HHF Wasatch Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired \| Property						15
Total consideration acquired						$ 262,000
Contribution of company to joint venture as share in capital						$ 51,500
Company common ownership interest	20.00%			20.00%										20.00%	20.00%
Purchase price of business to be acquired	$ 22,500
Life Storage-SERS Storage LLC [Member]
Schedule of Equity Method Investments [Line Items]
Total consideration acquired															$ 51,700
Distributions from unconsolidated joint ventures											$ 2,800