Organization - Additional Information (Detail)	3 Months Ended
Mar. 31, 2023 Property State $ / shares shares	Dec. 31, 2022 shares
Organization [Line Items]
Number of self-storage properties owned and managed \| Property	1,210
Number of states in which self-storage properties owned and managed \| State	37
Number of properties managed under joint ventures \| Property	142
Number of properties managed with no ownership \| Property	310
Fixed priority return on Preferred unitholders, Percentage	4.50%
Noncontrolling limited partnership unit redemption value	one common share or cash
Revenue [Member]
Organization [Line Items]
Number of self-storage properties owned and managed \| Property	1,210
Geographic Concentration Risk [Member] \| Texas [Member] \| Revenue [Member]
Organization [Line Items]
Concentration risk, percentage	15.00%
Geographic Concentration Risk [Member] \| Florida [Member] \| Revenue [Member]
Organization [Line Items]
Concentration risk, percentage	15.00%
Warehouse Anywhere LLC [Member]
Organization [Line Items]
Equity Method Investment, Ownership Percentage	83.00%
Life Storage LP [Member]
Organization [Line Items]
Units of redeemable noncontrolling interest in operating partnership \| shares	1,602,323	1,041,260
Conversion of preferred operating partnership units \| shares	2,332,706
Number of common operating partnership units issued (in shares) \| shares	561,063
Redeemable Preferred Stock [Member]
Organization [Line Items]
Preferred Stock, Par or Stated Value Per Share \| $ / shares	$ 25.00
Redeemable Preferred Stock [Member] \| Life Storage LP [Member]
Organization [Line Items]
Units of redeemable noncontrolling interest in operating partnership \| shares	1,190,407	3,523,113
Life Storage LP [Member]
Organization [Line Items]
Ownership interest	97.90%

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Redeemable non controlling interests disclosure.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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