Derivative Financial Instruments - Summary of Designated and Qualifying Hedged Items in Fair Value Hedges (Detail) $ in Thousands	Sep. 30, 2020 USD ($)
Derivative [Line Items]
Carrying Amount	$ 5,640
Hedging Fair Value Adjustment	555
Commercial Real Estate [Member]
Derivative [Line Items]
Carrying Amount	5,640
Hedging Fair Value Adjustment	$ 555

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959

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