Income Taxes - Additional Information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) subsidiary
Income Tax [Line Items]
Tax benefit related to remeasurment of deferred tax balance and valuation allowance \| $	$ 8,606
Extra Space Management, Inc
Income Tax [Line Items]
Number of taxable REIT subsidiaries \| subsidiary	1

Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense

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