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Investment in Joint Ventures - Summary of Company's Unconsolidated Joint Ventures (Parenthetical) (Detail) $ in Thousands		1 Months Ended								6 Months Ended
	Apr. 01, 2021 USD ($)	Oct. 31, 2022 USD ($)	Jun. 30, 2022 USD ($) Property	Apr. 30, 2022 USD ($)	Dec. 31, 2021 USD ($) Property	Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($) Property	Sep. 30, 2020 USD ($) Property	Jun. 30, 2022 USD ($) Property	Jun. 30, 2021 USD ($)	Apr. 30, 2021 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired \| Property										31
Total consideration acquired										$ 51,700
Distributions from unconsolidated joint ventures							$ 2,800			8,125	$ 6,772
Rent paid during the period										800	700
Mortgages payable			$ 36,646		$ 37,030					36,646
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			$ 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
Total consideration acquired			31,700
Additional contribution			$ 6,700
Company common ownership interest			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%
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%
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%
SNL Orix 1200 McDonald Ave., LLC [Member] \| Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Company common ownership interest							86.00%
Joint Ventures with Properties in Development Stage [Member]
Schedule of Equity Method Investments [Line Items]
Number Of joint ventures \| Property										7
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
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
Joint Ventures with Properties in Development Stage [Member] \| Tucson, AZ [Member]
Schedule of Equity Method Investments [Line Items]
Number of joint venture developing self-storage facilities \| Property			1							1
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
Joint Ventures with Properties in Development Stage [Member] \| Common Stock Shares [Member]
Schedule of Equity Method Investments [Line Items]
Total consideration acquired										$ 19,400