Loans and Allowance for Loan Losses - Summary of TDRs (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) TDR	Sep. 30, 2019 USD ($) TDR	Sep. 30, 2020 USD ($) TDR	Sep. 30, 2019 USD ($) TDR
Recreation [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans \| TDR	18	40	57	276
Pre- Modification Investment	$ 254	$ 587	$ 722	$ 4,109
Post- Modification Investment	$ 229	$ 505	$ 510	$ 2,619
Medallion [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Loans \| TDR	3	1	33	10
Pre- Modification Investment	$ 448	$ 758	$ 14,089	$ 4,041
Post- Modification Investment	$ 448	$ 758	$ 14,089	$ 4,041

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=121611835&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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