Debt - Additional Information (Detail) $ in Millions																								1 Months Ended	9 Months Ended
		Sep. 27, 2024 CAD ($)	Aug. 30, 2024 CAD ($)	Jul. 29, 2024 USD ($)	May 31, 2024	May 24, 2024	May 22, 2024	May 03, 2024 CAD ($)	Jan. 01, 2024	Sep. 28, 2023 USD ($)	Jun. 15, 2023 CAD ($)	May 19, 2023 CAD ($)	May 10, 2023 CAD ($)	May 04, 2023 CAD ($)	Apr. 13, 2023 USD ($)	Jan. 31, 2023 CAD ($)	Dec. 20, 2022 CAD ($)	Sep. 20, 2022 CAD ($)	May 26, 2022 USD ($)	May 17, 2022 USD ($)	Apr. 26, 2022 USD ($)	Dec. 30, 2021 USD ($)	Nov. 30, 2021 USD ($) SpecialEntity	May 31, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 25, 2024 USD ($)	Jun. 28, 2024 USD ($)	Mar. 28, 2024 USD ($)	Jun. 15, 2023 USD ($)	Dec. 20, 2022 USD ($)	Dec. 19, 2022 USD ($)	Jul. 08, 2021 USD ($)
Line Of Credit Facility [Line Items]
Weighted average interest rate																									7.42%
SmartStop Delayed Draw Mezzanine Loan Agreement
Line Of Credit Facility [Line Items]
Repaid outstanding balance																								$ 50,000,000
Huntington Credit Facility
Line Of Credit Facility [Line Items]
Number of Special Purpose Entities | SpecialEntity																							3
Line of credit facility, maximum borrowing capacity															$ 107,600,000								$ 50,000,000
Term loan maturity date																									Nov. 30, 2025
Applicable interest rate	[1]																								7.46%
Line of credit facility, amount borrowed															$ 12,500,000						$ 12,900,000	$ 14,700,000	$ 22,400,000
Debt Instrument, Interest Rate, Effective Percentage																									7.46%
Huntington Credit Facility | Floor
Line Of Credit Facility [Line Items]
Applicable interest rate										3.25%
Huntington Credit Facility | Secured Overnight Financing Rate
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate										2.61%
Interest rate term																									one month
Huntington Credit Facility | SOFR
Line Of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Effective Percentage															2.92%										0.77%			0.50%
Huntington Credit Facility | Second Amendment
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity																				$ 100,000,000
Line of credit facility, amount borrowed																			$ 30,600,000	14,500,000
Line of credit, additional borrowing capacity																				$ 50,000,000
Huntington Credit Facility | Interest Rate Swap Agreement | Secured Overnight Financing Rate
Line Of Credit Facility [Line Items]
Applicable interest rate															4.01%
Huntington Credit Facility | Interest Rate Cap
Line Of Credit Facility [Line Items]
Notional amount										$ 47,600,000					$ 47,600,000
Huntington Credit Facility | Interest Rate Cap | Secured Overnight Financing Rate
Line Of Credit Facility [Line Items]
Applicable interest rate										1.10%					2.60%
Huntington Credit Facility | Interest Rate Swap Agreement One
Line Of Credit Facility [Line Items]
Notional amount															$ 38,000,000											$ 38,000,000		$ 38,000,000
Huntington Credit Facility | Interest Rate Swap Agreement Two
Line Of Credit Facility [Line Items]
Notional amount															$ 22,000,000											$ 22,000,000		$ 22,000,000
Skymar Loan
Line Of Credit Facility [Line Items]
Term loan maturity date																																Aug. 01, 2024
Applicable interest rate																																4.125%
Mortgage loan, amount																																$ 4,800,000
Loans from SmartStop OP, L.P. | SmartStop Delayed Draw Mezzanine Loan Agreement | Cambridge Property
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity																														$ 55,000,000	$ 45,000,000
Loans from SmartStop OP, L.P. | SmartStop Delayed Draw Mezzanine Loan Agreement | Secured Overnight Financing Rate | Cambridge Property
Line Of Credit Facility [Line Items]
Debt instrument, description of variable rate basis																	SOFR plus 3%
Loans from SmartStop OP, L.P. | SmartStop Bridge Loan Agreement
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity																													$ 15,000,000
Commitment fee percentage											1.00%
Applicable interest rate																									8.96%
Line of credit facility, amount borrowed				$ 8,000,000
Debt instrument, maturity date, description																									On December 8, 2023, we exercised the option to extend the maturity date for an additional year, through December 31, 2024.
Line of credit facility, available capacity																									$ 2,000,000
Loans from SmartStop OP, L.P. | SmartStop Bridge Loan Agreement | Secured Overnight Financing Rate
Line Of Credit Facility [Line Items]
Debt instrument, description of variable rate basis									SOFR plus 4.00%		SOFR plus 3.00%
Debt instrument variable interest rate									4.00%		3.00%
Loans from SmartStop OP, L.P. | Minimum | SmartStop Bridge Loan Agreement
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity																											$ 15,000,000
Loans from SmartStop OP, L.P. | Maximum | SmartStop Delayed Draw Mezzanine Loan Agreement | Bradenton Property and Apopka Property
Line Of Credit Facility [Line Items]
Loan in connection with acquisition of Bradenton Property and Apopka Property																						$ 45,000,000
Loans from SmartStop OP, L.P. | Maximum | SmartStop Bridge Loan Agreement
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity																											$ 25,000,000
National Bank of Canada Loan | Acquisition of North York Property
Line Of Credit Facility [Line Items]
Debt instrument carrying amount																$ 25.0
National Bank of Canada Loan | CDOR | Acquisition of North York Property
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate																2.40%
Interest rate term																one month
National Bank of Canada Loan | Interest Rate Swap Agreement | Acquisition of North York Property
Line Of Credit Facility [Line Items]
Notional amount																$ 25.0
Debt instrument maturity date																Jan. 31, 2025
Debt instrument, frequency of payment																monthly
Debt instrument amortization period																25 years
National Bank of Canada Loan | Interest Rate Swap Agreement | CDOR | Acquisition of North York Property
Line Of Credit Facility [Line Items]
Applicable interest rate																3.79%
National Bank of Canada | Burlington Property
Line Of Credit Facility [Line Items]
Term loan																		$ 16.5
National Bank of Canada | Cambridge Property
Line Of Credit Facility [Line Items]
Repaid outstanding balance		$ 0.1	$ 0.1					$ 0.4					$ 0.4
Term loan																	$ 15.5
National Bank of Canada | CDOR | Burlington Property
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate																		2.25%
Interest rate term																		one month
National Bank of Canada | CDOR | Cambridge Property
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate																	2.25%
Interest rate term																	one month
National Bank of Canada | CORRA | Burlington Property
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate							2.25%
National Bank of Canada | CORRA | Cambridge Property
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate							2.25%
National Bank of Canada | CORRA | Acquisition of North York Property
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate							2.40%
National Bank of Canada | Interest Rate Swap Agreement | Burlington Property
Line Of Credit Facility [Line Items]
Notional amount																		$ 16.5
Debt instrument maturity date																		Sep. 20, 2025
Debt instrument, frequency of payment																		monthly
Debt instrument amortization period																		25 years
National Bank of Canada | Interest Rate Swap Agreement | Cambridge Property
Line Of Credit Facility [Line Items]
Notional amount																	$ 15.5
Debt instrument maturity date																	Dec. 20, 2025
Debt instrument, frequency of payment																	monthly
Debt instrument amortization period																	25 years
National Bank of Canada | Interest Rate Swap Agreement | CDOR | Burlington Property
Line Of Credit Facility [Line Items]
Applicable interest rate																		4.02%
National Bank of Canada | Interest Rate Swap Agreement | CDOR | Cambridge Property
Line Of Credit Facility [Line Items]
Applicable interest rate																	3.83%													3.83%
National Bank of Canada | Interest Rate Swap Agreement | CORRA | Burlington Property
Line Of Credit Facility [Line Items]
Applicable interest rate							0.30%
National Bank of Canada | Interest Rate Swap Agreement | CORRA | Cambridge Property
Line Of Credit Facility [Line Items]
Applicable interest rate							0.30%
National Bank of Canada | Interest Rate Swap Agreement | CORRA | Acquisition of North York Property
Line Of Credit Facility [Line Items]
Applicable interest rate							0.30%
Bank of Montreal Loan
Line Of Credit Facility [Line Items]
Debt instrument, initial term														2 years
Debt instrument carrying amount														$ 21.6
Debt instrument maturity date														May 04, 2025
Extension option period														1 year
Bank of Montreal Loan | CDOR
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate														2.50%
Interest rate term														one-month
Bank of Montreal Loan | CORRA
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate						2.50%
Bank of Montreal Loan | Interest Rate Swap Agreement
Line Of Credit Facility [Line Items]
Notional amount														$ 21.6
Bank of Montreal Loan | Interest Rate Swap Agreement | CDOR
Line Of Credit Facility [Line Items]
Applicable interest rate														4.47%
Bank of Montreal Loan | Interest Rate Swap Agreement | CORRA
Line Of Credit Facility [Line Items]
Applicable interest rate						0.30%
First National Loan
Line Of Credit Facility [Line Items]
Term loan maturity date																									Jun. 01, 2025
Applicable interest rate	[2]																								8.60%
Debt instrument, initial term												2 years
Debt instrument carrying amount												$ 8.8
Debt instrument maturity date												Jun. 01, 2025
First National Loan | Royal Bank of Canada Prime Rate
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate												1.90%
National Bank of Canada - Ontario Loan
Line Of Credit Facility [Line Items]
Debt instrument carrying amount											$ 127.2
Debt instrument maturity date											Jun. 15, 2025
Debt instrument, frequency of payment											monthly
Debt instrument amortization period											25 years
National Bank of Canada - Ontario Loan | CDOR
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate											2.60%
Interest rate term											one month
National Bank of Canada - Ontario Loan | CORRA
Line Of Credit Facility [Line Items]
Debt instrument variable interest rate					2.60%
National Bank of Canada - Ontario Loan | Interest Rate Swap Agreement
Line Of Credit Facility [Line Items]
Notional amount											$ 127.2
National Bank of Canada - Ontario Loan | Interest Rate Swap Agreement | CDOR
Line Of Credit Facility [Line Items]
Applicable interest rate											4.73%																		4.73%
National Bank of Canada - Ontario Loan | Interest Rate Swap Agreement | CORRA
Line Of Credit Facility [Line Items]
Applicable interest rate					0.30%
Extended Maturity | Huntington Credit Facility
Line Of Credit Facility [Line Items]
Term loan maturity date										Nov. 30, 2027
Extended Maturity | Loans from SmartStop OP, L.P. | SmartStop Delayed Draw Mezzanine Loan Agreement | Cambridge Property
Line Of Credit Facility [Line Items]
Debt instrument maturity date																	Dec. 30, 2023
Extended Maturity | Loans from SmartStop OP, L.P. | SmartStop Bridge Loan Agreement
Line Of Credit Facility [Line Items]
Term loan maturity date																											Dec. 31, 2025

[1] This variable rate loan encumbers 12 properties (Phoenix I, Phoenix II, Surprise, Bradenton, Apopka, Vancouver WA, Portland, Newark, Levittown, Chandler, St. Johns and Oxford). We entered into interest rate swap agreements and an interest rate cap that fixes Secured Overnight Financing Rate ("SOFR") at 0.77% until the maturity of the loan.

[2] This variable rate loan encumbers our Edmonton, AB property and the amount shown above is in USD based on the foreign exchange rate in effect as of September 30, 2024 and December 31, 2023, respectively.