v3.21.2

Business Description - Additional Information (Detail)				3 Months Ended						9 Months Ended
	Sep. 21, 2020 $ / shares shares	Sep. 18, 2020 $ / shares shares	Feb. 07, 2020 USD ($)	Sep. 30, 2021 USD ($) State Property $ / shares shares	Jun. 30, 2021 shares	Mar. 31, 2021 shares	Sep. 30, 2020 USD ($) shares	Jun. 30, 2020 shares	Mar. 31, 2020 shares	Sep. 30, 2021 USD ($) State Property $ / shares shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 $ / shares shares
Business Description [Line Items]
Date of incorporation										Oct. 18, 2007
Number of leased commercial properties owned | Property				696						696
Internalization fees | $							$ 1,929,000				$ 3,523,000
Common stock, shares outstanding		26,944,000		161,255,000						161,255,000		108,609,000
Common stock, par value | $ / shares		$ 0.001		$ 0.00025						$ 0.00025		$ 0.00025
Issuance of shares of common stock, shares										1,089
IPO
Business Description [Line Items]
Common stock, par value | $ / shares	$ 0.00025
Issuance of shares of common stock, shares	37,000,000
Offering price | $ / shares	$ 17.00
Common Stock
Business Description [Line Items]
Stock split		4
Issuance of shares of common stock, shares				957,000	11,659,000	211,000	341,000	11,000	293,000
Property Management Agreement and Asset Management Agreement | Merger Agreement
Business Description [Line Items]
Internalization fees | $			$ 0
U.S.
Business Description [Line Items]
Number of leased commercial properties owned | Property				695						695
Number of States in which properties located | State				42						42
British Columbia, Canada
Business Description [Line Items]
Number of leased commercial properties owned | Property				1						1

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