Accelerated depreciation reduced basic and diluted earnings per share.

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- Definition

Cash payments to acquire real estate.

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- Definition

Estimate increase in depreciation expense due to facility replacement.

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- Definition

Estimate increase in depreciation expense due to facility replacement during remainder of fiscal year.

+ References

No definition available.

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- Definition

Increase in depreciation expense due to facility replacement.

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- Definition

Noncash or part noncash acquisition, other assets acquired (liabilities assumed).

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No definition available.

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- Definition

Number of properties acquired.

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No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Investment in Storage Facilities and Intangible Assets - Additional Information (Detail) $ / shares in Units, $ in Thousands	3 Months Ended				9 Months Ended
	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($) Property $ / shares	Mar. 31, 2020 USD ($) Property	Sep. 30, 2019 USD ($) $ / shares	Sep. 30, 2020 USD ($) Property $ / shares	Sep. 30, 2019 USD ($) $ / shares
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property					31
Cash payment for property acquisition					$ 417,930
Received return on investment					9,246	$ 7,419
Net other liabilities assumed					$ 1,700
Amortization period for in-place customer leases on a straight-line basis					12 months
Amortization expense related to in-place customer leases		$ 1,100		$ 800	$ 3,800	1,700
Increase in depreciation expense due to facility replacement		4,400		$ 300	4,400	$ 1,100
Estimate increase in depreciation expense due to facility replacement during remainder of 2020		$ 1,100			$ 1,100
Accelerated depreciation reduced basic and diluted earnings per share \| $ / shares		$ 0.09			$ 0.09	$ 0.02
Maximum [Member]
Investment Holdings [Line Items]
Accelerated depreciation reduced basic and diluted earnings per share \| $ / shares				$ 0.01
Forecast [Member]
Investment Holdings [Line Items]
Estimate increase in depreciation expense due to facility replacement	$ 1,100
191 III Life Storage Holdings LLC [Member]
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property			6
Company common ownership interest			20.00%
Cash payment for property acquisition			$ 124,200
Received return on investment			$ 8,400
Sovran HHF Storage Holdings LLC and Sovran HHF Storage Holdings II LLC [Member]
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property		25
Cash payment for property acquisition		$ 293,700
Received return on investment		$ 32,700
Sovran HHF Storage Holdings LLC [Member]
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property		17
Company common ownership interest		20.00%			20.00%
Sovran HHF Storage Holdings II LLC [Member]
Investment Holdings [Line Items]
Number of storage facilities acquired \| Property		8
Company common ownership interest		15.00%			15.00%