Additional funds available to be advanced in connection with impaired loans.

No definition available.

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- Definition

Delinquent period for charging down commercial and agricultural credits.

+ References

No definition available.

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- Definition

Delinquent period for charging down consumer loans

+ References

No definition available.

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- Definition

Financing receivables impaired number of troubled debt restructuring write down.

+ References

No definition available.

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- Definition

Maximum time for reevaluation.

+ References

No definition available.

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- Definition

Re evaluation period for real estate.

+ References

No definition available.

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- Definition

Unsecured consumer loans credit card credits and overdraft.

+ References

No definition available.

+ Details

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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

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

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

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL49126937-111524

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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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Loans (Impaired Loans) - Additional Information (Detail)	1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	May 31, 2020 Loan	Sep. 30, 2020 USD ($) Loan	Jun. 30, 2020 Contract	Sep. 30, 2019 USD ($) Contract	Sep. 30, 2020 USD ($) Contract Loan	Sep. 30, 2019 USD ($) Contract Loan	Dec. 31, 2019 USD ($) Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Additional funds available to be advanced in connection with impaired loans		$ 1,200,000			$ 1,200,000
Impaired loans classified as troubled debt restructured		$ 6,400,000		$ 1,100,000	$ 6,400,000	$ 1,100,000	$ 1,000,000.0
Number of contracts modified \| Loan		1			6		5
TDR impaired loans paid off \| Loan	1					0
TDR loans, subsequently defaulted during the period		0		0	0	0
Maximum time for re-evaluation (in months)					12 months
Re-evaluation period for real estate					2 years
Unsecured consumer loans, credit card credits and overdraft lines of credit reach						90 days
Delinquent period for charging down consumer loans						120 days
Delinquent period for charging down commercial and agricultural credits						120 days
Foreclosed residential real estate property		$ 206,000			$ 206,000		$ 214,000
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired loans classified as troubled debt restructured		481,000			$ 481,000
Number of contracts modified \| Contract					2
TDR impaired loans paid off \| Loan					1
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract				1		1
Foreclosed residential real estate property		71,000		$ 187,000	$ 71,000	$ 187,000
Residential real estate properties foreclosure proceedings		$ 849,000		$ 379,000	$ 849,000	$ 379,000
Principal Forgiveness [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract					0
Payment Changes from Monthly Payment to Principal and Interest at Maturity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract					2
Loan maturity date					Jun. 19, 2020
Rate Concession Along With the Amortization Extended [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts modified \| Contract			3