Increase (decrease) in loans outstanding.

No definition available.

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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

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the best estimate at the acquisition date of the contractual cash flows not expected to be collected, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

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-SubTopic 20
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- Definition

Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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.

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- Definition

The net amount of operating interest income (expense).

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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Loans - Additional Information (Detail)	3 Months Ended								12 Months Ended
Loans - Additional Information (Detail)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) contract	Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 45,436,000				$ 23,451,000				$ 45,436,000	$ 23,451,000	$ 21,247,000	$ 16,553,000
Provision for loan losses	18,961,000	$ 1,000,000	$ 7,031,000	$ 5,055,000	975,000	$ 136,000	$ 570,000	$ 573,000	32,047,000	2,254,000	4,313,000
Net interest income	28,113,000	$ 28,262,000	$ 27,365,000	$ 27,420,000	26,920,000	$ 26,562,000	$ 26,905,000	$ 25,116,000	$ 111,160,000	$ 105,503,000	97,046,000
Number of loans modified as troubled debt restructuring \| contract									1	1
Loans modified as troubled debt restructuring, Amount	311,000				167,000				$ 311,000	$ 167,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	8,113,000				6,725,000				8,113,000	6,725,000	5,981,000	4,266,000
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	27,957,000				7,166,000				27,957,000	7,166,000	$ 7,587,000	$ 6,068,000
Increase loans outstanding									3,995,000
Classified and Criticized Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase loans outstanding									(12,291,000)
Nonfarm, nonresidential \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase loans outstanding									12,013,000
MidSouth And Civic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable carrying amount	58,745,000								58,745,000
Unpaid principal balance	59,471,000								59,471,000
Estimated credit discount	726,000								726,000
Allowance for loan losses	77,000								77,000
PCI Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 22,000				$ 0				$ 22,000	$ 0