Commitments and Contingencies - Additional Information (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Agreement	Dec. 31, 2018 USD ($) Agreement	Dec. 31, 2017 USD ($) Agreement
Loss Contingencies [Line Items]
Number of lease agreements assumed in acquisitions \| Agreement	6	6	6
Tenant improvement allowances in acquisitions	$ 2,517	$ 0	$ 2,777
Minimum
Loss Contingencies [Line Items]
Non-cancellable operating leases term	2034
Maximum
Loss Contingencies [Line Items]
Maximum aggregate amount	$ 12,300
Non-cancellable operating leases term	2066

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12021-110248

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