| Cover - shares | 3 Months Ended | |
| Mar. 31, 2024 | Apr. 30, 2024 |
| Cover [Abstract] | | |
| Document Type | 10-Q/A | |
| Document Quarterly Report | true | |
| Document Period End Date | Mar. 31, 2024 | |
| Document Transition Report | false | |
| Entity File Number | 001-32269 | |
| Entity Registrant Name | EXTRA SPACE STORAGE INC. | |
| Entity Incorporation, State or Country Code | MD | |
| Entity Tax Identification Number | 20-1076777 | |
| Entity Address, Address Line One | 2795 East Cottonwood Parkway, Suite 300 | |
| Entity Address, City or Town | Salt Lake City | |
| Entity Address, State or Province | UT | |
| Entity Address, Postal Zip Code | 84121 | |
| City Area Code | 801 | |
| Local Phone Number | 365-4600 | |
| Title of 12(b) Security | Common Stock, $0.01 par value | |
| Trading Symbol | EXR | |
| Security Exchange Name | NYSE | |
| Entity Current Reporting Status | Yes | |
| Entity Interactive Data Current | Yes | |
| Entity Filer Category | Large Accelerated Filer | |
| Entity Small Business | false | |
| Entity Emerging Growth Company | false | |
| Entity Shell Company | false | |
| Entity Common Stock, Shares Outstanding | | 211,725,246 |
| Amendment Flag | true | |
| Document Fiscal Year Focus | 2024 | |
| Document Fiscal Period Focus | Q1 | |
| Entity Central Index Key | 0001289490 | |
| Current Fiscal Year End Date | --12-31 | |
| Amendment Description | This Amendment No. 1 on Form 10-Q/A (this “Amendment”) amends the Quarterly Report on Form 10-Q for the quarter ended March 31, 2024 originally filed by Extra Space Storage Inc., a Maryland corporation (“we,” “our,” “us” or the “Company”), with the Securities and Exchange Commission (“SEC”) on May 3, 2024 (the “Original Filing”). We are filing this Amendment solely to (a) amend Item 5 of Part II of the Original Filing to include information concerning a Rule 10b5-1 trading arrangement adopted by our Chief Executive Officer on March 1, 2024 that was inadvertently omitted from the Original Filing and (b) amend Item 6 of Part II of the Original Filing to include (i) new certifications of our Chief Executive Officer and Chief Financial Officer, as Exhibits 31.1 and 31.2, pursuant to Rule 13a-14(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Because no financial statements have been included in this Amendment and this Amendment does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4 and 5 of the certifications have been omitted. We are not furnishing new certifications under Section 906 of the Sarbanes-Oxley Act of 2002 because no financial statements are being filed with this Amendment. The complete text of Item 5 of Part II has been set forth in its entirety in accordance with Rule 12b-15 under the Exchange Act.Except as described above, no other changes have been made to the Original Filing. The Original Filing continues to speak as of the date of the Original Filing, and we have not updated the disclosures contained therein to reflect any events occurring subsequent to the filing of the Original Filing other than as expressly indicated in this Amendment. Accordingly, this Amendment should be read in conjunction with the Original Filing and our other filings made with the SEC subsequent to May 3, 2024, including any amendments to those filings. | |
