Description of the Plan (Details) - EBP 001 - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Description of Plan [Line Items]
Minimum participant age	18 years
Participant compensation matched, minimum service period	3 months
Maximum annual compensation to total compensation, percentage	75.00%
Catch-up contribution, minimum age	50 years
Minimum borrowing, amount	$ 1,000
Maximum borrowing, amount	$ 50,000
Maximum borrowing, to total account, percentage	50.00%
General loan, borrowing term	5 years
Primary residence, borrowing term	10 years
Involuntary cash-out limit	$ 7,000
Involuntary cash-out minimum	1,000
Forfeited nonvested account	4,676	$ 20,410
Forfeited nonvested account, excess contributions	14,898
Forfeited nonvested account, decrease from administrative expense	$ 438,824
Threshold One
EBP, Description of Plan [Line Items]
Matching percentage	100.00%
Participant compensation matched, percentage	3.00%
Threshold Two
EBP, Description of Plan [Line Items]
Matching percentage	50.00%
Participant compensation matched, percentage	2.00%
Threshold Three
EBP, Description of Plan [Line Items]
Participant compensation matched, percentage	4.00%

EBP, Forfeited Nonvested Account, Excess Contributions

No definition available.

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Period Type:	duration

- Definition

EBP, Involuntary Cash-out, Maximum

+ References

No definition available.

+ Details

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- Definition

EBP, Involuntary Cash-out, Minimum

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

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- Definition

EBP, Participant Contribution, After Tax, Catch-Up Contribution Eligibility, Minimum Age

+ References

No definition available.

+ Details

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- Definition

EBP, Participant Contribution, After Tax, Maximum Annual Contribution to Eligible Compensation, Percentage

+ References

No definition available.

+ Details

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- Definition

EBP, Participant Contribution, After Tax, Minimum Participant Age

+ References

No definition available.

+ Details

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Namespace Prefix:	exr_
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Period Type:	duration

- Definition

EBP, Requisite Service Period

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Period Type:	duration

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from administrative expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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- Details

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- Details

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