Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
YTD Losses, Loans held for sale			$ (2)	$ (4)
YTD Losses, Individually assessed loans			568
YTD Losses, Impaired Loans				1,831
YTD Losses, OREO			(440)	(785)
YTD Losses, Mortgage servicing rights	$ (710)	$ (710)	(710)
Loans held for sale	611,277	611,277	611,277	384,375
Individually assessed loans				123,505
OREO	29,947	29,947	29,947	15,515
Mortgage servicing rights	20,200	20,200	20,200
Mortgage Servicing Rights [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
YTD Losses, Mortgage servicing rights			(710)
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	14,707	14,707	14,707	3,139
Individually assessed loans	59,488	59,488	59,488
Impaired Loans				68,213
OREO	29,947	29,947	29,947	15,515
Fair Value, Measurements, Nonrecurring [Member] \| Mortgage Servicing Rights [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing rights	20,200	20,200	20,200
Fair Value, Measurements, Nonrecurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	0	0	0	0
Individually assessed loans	0	0	0
Impaired Loans				0
OREO	0	0	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Mortgage Servicing Rights [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing rights	0	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	14,707	14,707	14,707	3,139
Individually assessed loans	49,732	49,732	49,732
Impaired Loans				55,792
OREO	29,898	29,898	29,898	15,495
Fair Value, Measurements, Nonrecurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Mortgage Servicing Rights [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing rights	0	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans held for sale	0	0	0	0
Individually assessed loans	9,756	9,756	9,756
Impaired Loans				12,421
OREO	49	49	49	$ 20
Fair Value, Measurements, Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Mortgage Servicing Rights [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing rights	$ 20,200	$ 20,200	$ 20,200

Financing receivable individually evaluated for impairment gain loss.

No definition available.

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- Definition

Losses (gains) recognized on loans held for sale including, but not limited to, mortgage loans and financing receivables due to a change in the fair value on nonrecurring basis.

+ References

No definition available.

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Losses incurred due to a change in the fair value of loans within the allowance for loan losses where it is probable that all amounts due according to the contractual terms of the loan agreement will not be collected.

+ References

No definition available.

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- Definition

Losses incurred due to a change in the fair value of other real estate owned properties acquired through foreclosure or other settlement of loans.

+ References

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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

No definition available.

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The balance of financing receivables that were individually evaluated for impairment.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5162-111524

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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- Definition

The net increase (decrease) in the valuation allowance for servicing assets subsequently measured using the amortization method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
-Section 50
-Paragraph 4
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