Acquisitions of Rental Property - Acquisitions of Rental Property Closed (Parenthetical) - (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Business Combinations [Abstract]
Acquisition costs capitalized	$ 3.1	$ 3.0
Tenant's building expansion	$ 17.4

Amount of deferred policy acquisition cost capitalized on contract remaining in force.

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Name:	us-gaap_DeferredPolicyAcquisitionCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant