Incentive Plans - Summary of Activity Related to Shares of Restricted Common Stock (Parenthetical) (Detail)	9 Months Ended
Sep. 30, 2020 shares
Restricted Stock [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Number of RSUs issued in connection with dividend participation rights	28,948

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration