Real Estate and Other Activities - Disposals - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) Facility	Mar. 31, 2020 USD ($) Property
Business Combinations [Abstract]
Number of facilities sold \| Facility	1
Number of properties sold \| Property		4
Proceeds from sale of facilities	$ 11.0
Gain (loss) on real estate dispositions	$ 1.0	$ 1.3

Cash received for the sale of real estate that is not part of an investing activity during the current period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

Name:	us-gaap_ProceedsFromSaleOfRealEstate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration