Fair Value Measurement - Estimated Fair Values of Financial Instruments that are Reported at Amortized Cost in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Financial assets:
Cash and due from banks	$ 106,939	$ 119,781
Cash at Federal Reserve and other banks	68,643	107,752
Securities held to maturity	412,524	444,936
Loans held for sale	5,875	3,687
Financial liabilities:
Other borrowings	13,292	15,839
Junior subordinated debt	57,132	57,042
Level 3 [Member] \| Overdraft Privilege Commitments [Member]
Off-balance sheet:
Contract amount, Off-balance sheet	108,941	111,956
Level 3 [Member] \| Standby Letters of Credit [Member]
Off-balance sheet:
Contract amount, Off-balance sheet	11,338	11,346
Level 3 [Member] \| Commitments [Member]
Off-balance sheet:
Contract amount, Off-balance sheet	1,201,892	1,192,054
Fair Value [Member] \| Level 3 [Member]
Financial assets:
Loans, net	4,057,792	4,006,986
Financial liabilities:
Junior subordinated debt	56,209	62,610
Fair Value [Member] \| Level 3 [Member] \| Overdraft Privilege Commitments [Member]
Off-balance sheet:
Fair value, Off-balance sheet	1,089	1,120
Fair Value [Member] \| Level 3 [Member] \| Standby Letters of Credit [Member]
Off-balance sheet:
Fair value, Off-balance sheet	113	113
Fair Value [Member] \| Level 3 [Member] \| Commitments [Member]
Off-balance sheet:
Fair value, Off-balance sheet	12,019	11,921
Fair Value [Member] \| Level 1 [Member]
Financial assets:
Cash and due from banks	106,939	119,781
Cash at Federal Reserve and other banks	68,643	107,752
Fair Value [Member] \| Level 2 [Member]
Financial assets:
Securities held to maturity	415,276	437,370
Loans held for sale	5,875	4,616
Financial liabilities:
Deposits	5,341,105	5,362,173
Other borrowings	13,292	15,839
Carrying Amount [Member] \| Level 3 [Member]
Financial assets:
Loans, net	4,070,819	3,989,432
Financial liabilities:
Junior subordinated debt	57,132	57,042
Carrying Amount [Member] \| Level 1 [Member]
Financial assets:
Cash and due from banks	106,939	119,781
Cash at Federal Reserve and other banks	68,643	107,752
Carrying Amount [Member] \| Level 2 [Member]
Financial assets:
Securities held to maturity	412,524	444,936
Restricted equity securities	17,250	17,250
Loans held for sale	5,875	3,687
Financial liabilities:
Deposits	5,342,173	5,366,466
Other borrowings	$ 13,292	$ 15,839

Cash at federal reserve and other banks.

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Off balance sheet.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount of restricted investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Publisher FASB
-Name Accounting Standards Codification
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The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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The face amount of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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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.

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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