Disposal Group, Including Discontinued Operation, Consideration, Partner Capital Units

No definition available.

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- Definition

Increase in payments due to sellers.

+ References

No definition available.

+ Details

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- Definition

Number of operating stores business acquired.

+ References

No definition available.

+ Details

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- Definition

Number of stores sold.

+ References

No definition available.

+ Details

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Namespace Prefix:	exr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Property Acquisition And Dispositions [Line Items]

+ References

No definition available.

+ Details

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2443-110228

+ Details

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Balance Type:	credit
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- Definition

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Store Acquisitions - Additional Information (Detail) $ in Thousands			6 Months Ended	12 Months Ended
	Apr. 20, 2016 USD ($) store	Apr. 01, 2016 USD ($) store shares	Jun. 30, 2016 USD ($)	Dec. 31, 2014 store
Disposal of Texas Store, April 1, 2016 [Member]
Property Acquisition And Dispositions [Line Items]
Number of stores sold \| store		1
Store Dispositions [Member] \| Disposal of Texas Store, April 1, 2016 [Member]
Property Acquisition And Dispositions [Line Items]
OP Units received for store disposal (in units) \| shares		85,452
Value of OP Units received for store disposal		$ 7,689
Gain on disposal of real estate		$ 93
Store Dispositions [Member] \| Disposal of Ohio and Indiana Stores, April 20, 2016 [Member]
Property Acquisition And Dispositions [Line Items]
Number of stores sold \| store	7
Gain on disposal of real estate	$ 11,265
Proceeds from sale of real estate	$ 17,555
New Jersey And Virginia, 5 Stores Acquired in 2014 [Member]
Property Acquisition And Dispositions [Line Items]
Number of operating stores acquired \| store				5
Increase in payments due to sellers resulting from higher rental income of properties			$ 1,544