Securities Sold under Agreements to Repurchase - Additional Information (Detail) - U.S. Government Sponsored Enterprises [Member] - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets Sold under Agreements to Repurchase [Line Items]
U.S. Government Sponsored Enterprise securities with a total amortized cost	$ 264,737,000	$ 160,576,000	$ 162,927,000
Fair value of the collateral repurchase agreement	$ 265,687,000	$ 156,369,000	$ 159,051,000

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.

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- Definition

The carrying value as of the balance sheet date of securities received as collateral from a counterparty that were re-pledged, sold, delivered or otherwise reused by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

+ References

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