Organization - Additional Information (Detail)					3 Months Ended						9 Months Ended
	May 28, 2021 USD ($)	Mar. 10, 2021 USD ($) shares	Feb. 26, 2021 USD ($)	Jan. 15, 2021 USD ($) $ / shares shares	Sep. 30, 2022 OperatingSelfStorageProperty UnconsolidatedRealEstateVenture Employee $ / shares shares	Jun. 30, 2022 shares	Mar. 31, 2022 shares	Sep. 30, 2021 shares	Jun. 30, 2021 shares	Mar. 31, 2021 shares	Sep. 30, 2022 USD ($) OperatingSelfStorageProperty UnconsolidatedRealEstateVenture Employee $ / shares shares	Dec. 31, 2021 $ / shares shares
Organization And Nature Of Operations [Line Items]
Date of formation of company											Oct. 14, 2020
Number of employees | Employee					0						0
Preferred Stock, shares authorized				200,000,000	200,000,000						200,000,000	200,000,000
Preferred Stock, par value | $ / shares				$ 0.001	$ 0.001						$ 0.001	$ 0.001
Shares issuable pursuant to distribution reinvestment plan | $			$ 20,000,000
Number of operating self storage properties owned | OperatingSelfStorageProperty					14						14
Percentage of non-voting economic interest owned by affiliates											10.00%
Number of unconsolidated real estate ventures | UnconsolidatedRealEstateVenture					2						2
Advisor purchased initial investment in operating partnership | $											$ 202,000
Distribution Reinvestment Plan
Organization And Nature Of Operations [Line Items]
Gross proceeds from issuance of common stock | $											$ 2,000,000.0
Maximum
Organization And Nature Of Operations [Line Items]
Common stock, value authorized | $			200,000,000
Class A Common Stock
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized					300,000,000						300,000,000	300,000,000
Common Stock, par value | $ / shares					$ 0.001						$ 0.001	$ 0.001
Class A Common Stock | Common Stock
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering					637,805	572,182
Class A Common Stock | Distribution Reinvestment Plan
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering											3,000
Class A Common Stock | Primary Offering | Maximum
Organization And Nature Of Operations [Line Items]
Common stock, value authorized | $	$ 1,000,000,000
Class A Common Stock | Pubic Offering
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized				300,000,000
Shares issuable pursuant to distribution reinvestment plan | $	95,000,000
Gross proceeds from issuance of common stock | $											$ 12,500,000
Common stock issued in connection with offering											1,200,000
Class P Common Stock
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized					30,000,000						30,000,000	30,000,000
Common Stock, par value | $ / shares					$ 0.001						$ 0.001	$ 0.001
Class P Common Stock | Common Stock
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering						109,890	5,430,060	1,512,411	1,936,508	5,666
Class P Common Stock | Distribution Reinvestment Plan
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering											200,000
Class P Common Stock | Pubic Offering
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized				30,000,000
Class P Common Stock | Private Offering
Organization And Nature Of Operations [Line Items]
Gross proceeds from issuance of common stock | $											$ 100,700,000
Class P Common Stock | Private Offering | Common Stock
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering											10,600,000
Class T Common Stock
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized					300,000,000						300,000,000	300,000,000
Common Stock, par value | $ / shares					$ 0.001						$ 0.001	$ 0.001
Class T Common Stock | Common Stock
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering					1,521,783	668,360
Class T Common Stock | Distribution Reinvestment Plan
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering											5,000
Class T Common Stock | Primary Offering | Maximum
Organization And Nature Of Operations [Line Items]
Common stock, value authorized | $	1,000,000,000
Class T Common Stock | Pubic Offering
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized				300,000,000
Shares issuable pursuant to distribution reinvestment plan | $	95,000,000
Gross proceeds from issuance of common stock | $											$ 21,900,000
Common stock issued in connection with offering											2,200,000
Class W Common Stock
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized					70,000,000						70,000,000	70,000,000
Common Stock, par value | $ / shares					$ 0.001						$ 0.001	$ 0.001
Class W Common Stock | Common Stock
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering					78,617	86,436
Class W Common Stock | Distribution Reinvestment Plan
Organization And Nature Of Operations [Line Items]
Common stock issued in connection with offering											1,000
Class W Common Stock | Primary Offering | Maximum
Organization And Nature Of Operations [Line Items]
Common stock, value authorized | $	1,000,000,000
Class W Common Stock | Pubic Offering
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized				70,000,000
Shares issuable pursuant to distribution reinvestment plan | $	$ 95,000,000
Gross proceeds from issuance of common stock | $											$ 1.6
Common stock issued in connection with offering											200,000
Articles of Incorporation
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized				30,000
Common Stock, par value | $ / shares				$ 0.001
Articles of Amendment and Restatement
Organization And Nature Of Operations [Line Items]
Common Stock, shares authorized				700,000,000
Common Stock, par value | $ / shares				$ 0.001
Strategic Storage Advisor IV, LLC
Organization And Nature Of Operations [Line Items]
Sale of common shares to advisor | $				$ 1,000
Advisor purchased initial investment in operating partnership | $				$ 1,000
Strategic Storage Advisor IV, LLC | Class A Common Stock
Organization And Nature Of Operations [Line Items]
Number of shares sold to advisor				110
Smartstop Storage Advisors LLC.
Organization And Nature Of Operations [Line Items]
Investment by affiliate in exchange for additional limited partnership interests | $			$ 1,000
Smartstop OP L P [Member]
Organization And Nature Of Operations [Line Items]
Equity ownership percentage					3.70%						3.70%
Advisor purchased a limited partnership interest in Operating Partnership, number of partnership units		549,451
Initial capital contribution | $		$ 5,000,000.0
Strategic Storage Operating Partnership VI, L.P.
Organization And Nature Of Operations [Line Items]
Equity ownership percentage					96.30%						96.30%
SmartCentres
Organization And Nature Of Operations [Line Items]
Equity ownership percentage					50.00%						50.00%
SmartStop REIT Advisors, LLC | Strategic Storage Advisor IV, LLC
Organization And Nature Of Operations [Line Items]
Percentage of economic interests owned by sponsor											90.00%
Percentage of voting membership interests owned by sponsor					100.00%						100.00%
SmartStop REIT Advisors, LLC | Strategic Storage Property Management VI, LLC
Organization And Nature Of Operations [Line Items]
Percentage of Property Management owned by sponsor											100.00%