Loans and Allowance for Loan Losses - Summary of Troubled Debt Restructurings (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) TDR	Dec. 31, 2018 USD ($) TDR
Recreation [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans \| TDR	294
Pre- Modification Investment	$ 4,433
Post- Modification Investment	$ 2,831
Medallion [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans \| TDR	71	11
Pre- Modification Investment	$ 31,376	$ 5,581
Post- Modification Investment	$ 31,385	$ 5,581

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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