Loans Held for Investment and Allowance for Credit Losses on Loans - Allowance for Credit Losses Outstanding by Impairment Methodology (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	$ 7,705
Collectively evaluated for impairment	46,533
Real Estate [Member] \| Non-residential Real Estate Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	900
Collectively evaluated for impairment	6,140
Real Estate [Member] \| Non-residential Real Estate Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	990
Collectively evaluated for impairment	10,167
Real Estate [Member] \| Residential Real Estate Permanent Mortgage [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	531
Collectively evaluated for impairment	2,856
Real Estate [Member] \| Residential Real Estate Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	2,026
Collectively evaluated for impairment	8,123
Consumer Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	343
Collectively evaluated for impairment	2,976
Commercial and Financial [Member] \| Non-consumer Non-real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	2,902
Collectively evaluated for impairment	12,439
Other Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Individually evaluated for impairment	13
Collectively evaluated for impairment	2,619
Acquired Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collectively evaluated for impairment	614
Pegasus Bank [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collectively evaluated for impairment	$ 599

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

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+ References

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