Number of properties acquired.

No definition available.

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- Definition

Purchase price of assets acquired.

+ References

No definition available.

+ Details

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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Balance Type:	credit
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Thousands						1 Months Ended	9 Months Ended
	Nov. 06, 2020 USD ($) Property	Nov. 05, 2020 USD ($) Property	Oct. 26, 2020 USD ($)	Oct. 09, 2020 USD ($)	Oct. 01, 2020 $ / shares	Sep. 30, 2020 Property	Sep. 30, 2020 USD ($) Property
Subsequent Event [Line Items]
Number of storage facilities acquired \| Property							31
Aggregate purchase price							$ 419,608
Self-storage Facilities [Member]
Subsequent Event [Line Items]
Number of storage facilities acquired \| Property						3
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend declared, date					Oct. 01, 2020
Dividend per common share \| $ / shares					$ 1.07
Dividend paid, date					Oct. 26, 2020
Dividend record, date					Oct. 13, 2020
Dividend paid			$ 52,000
Number of storage facilities acquired \| Property	5
Aggregate purchase price	$ 59,600
Subsequent Event [Member] \| Self-storage Facilities [Member]
Subsequent Event [Line Items]
Number of storage facilities acquired \| Property		1
Aggregate purchase price		$ 13,700
Subsequent Event [Member] \| Term Note Due August 5, 2021 [Member]
Subsequent Event [Line Items]
Repayments of term debt				$ 100,000