Organization - Additional Information (Detail)	9 Months Ended
Sep. 30, 2022 Property State $ / shares shares	Dec. 31, 2021 shares
Organization [Line Items]
Number of self-storage properties owned and managed	1,152
Number of states in which self-storage properties owned and managed \| State	37
Number of properties managed under joint ventures	133
Number of properties managed with no ownership	267
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	1,152
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	16.00%
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	1,041,510	960,708
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	3,523,113	3,590,603
Life Storage LP [Member]
Organization [Line Items]
Ownership interest	98.00%

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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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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 securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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