Securities Sold Under Agreement to Repurchase - Summary of Repurchase Agreement (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets Sold Under Agreements To Repurchase [Line Items]
Market value of securities pledged	$ 113,426	$ 131,394
Securities sold under agreement to repurchase	$ 81,736	$ 93,141
Market value pledged as a % of borrowings	139.00%	141.00%
Mortgage Backed Securities [Member]
Assets Sold Under Agreements To Repurchase [Line Items]
Market value of securities pledged	$ 112,973	$ 130,942
Securities sold under agreement to repurchase	$ 81,520	$ 92,953
Market value pledged as a % of borrowings	139.00%	141.00%
Municipal Securities [Member]
Assets Sold Under Agreements To Repurchase [Line Items]
Market value of securities pledged	$ 453	$ 451
Securities sold under agreement to repurchase	$ 216	$ 188
Market value pledged as a % of borrowings	209.00%	240.00%

Market value of securities pledged as a percentage of borrowings.

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- Definition

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.

+ References

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

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