Fair Value Measurement - Estimated Fair Values of Financial Instruments that are Reported at Amortized Cost in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financial assets:
Cash and due from banks	$ 87,138	$ 105,968
Cash at Federal Reserve and other banks	95,841	99,460
Securities held to maturity	496,035	514,844
Financial liabilities:
Other borrowings	65,041	122,166
Junior subordinated debt	56,905	56,858
Level 3 [Member] \| Overdraft Privilege Commitments [Member]
Off-balance sheet:
Contract amount, Off-balance sheet	101,411	98,260
Level 3 [Member] \| Standby Letters of Credit [Member]
Off-balance sheet:
Contract amount, Off-balance sheet	11,573	13,075
Level 3 [Member] \| Commitments [Member]
Off-balance sheet:
Contract amount, Off-balance sheet	1,001,059	933,542
Fair Value [Member] \| Level 3 [Member]
Financial assets:
Loans, net	3,025,636	2,992,225
Financial liabilities:
Junior subordinated debt	59,982	58,466
Fair Value [Member] \| Level 3 [Member] \| Overdraft Privilege Commitments [Member]
Off-balance sheet:
Fair value, Off-balance sheet	1,014	983
Fair Value [Member] \| Level 3 [Member] \| Standby Letters of Credit [Member]
Off-balance sheet:
Fair value, Off-balance sheet	116	131
Fair Value [Member] \| Level 3 [Member] \| Commitments [Member]
Off-balance sheet:
Fair value, Off-balance sheet	10,011	9,335
Fair Value [Member] \| Level 1 [Member]
Financial assets:
Cash and due from banks	87,138	105,968
Cash at Federal Reserve and other banks	95,841	99,460
Fair Value [Member] \| Level 2 [Member]
Financial assets:
Securities held to maturity	488,639	518,165
Loans held for sale	2,149	4,616
Financial liabilities:
Deposits	4,081,089	4,006,620
Other borrowings	65,041	122,166
Carrying Amount [Member] \| Level 3 [Member]
Financial assets:
Loans, net	3,039,760	2,984,842
Financial liabilities:
Junior subordinated debt	56,905	56,858
Carrying Amount [Member] \| Level 1 [Member]
Financial assets:
Cash and due from banks	87,138	105,968
Cash at Federal Reserve and other banks	95,841	99,460
Carrying Amount [Member] \| Level 2 [Member]
Financial assets:
Securities held to maturity	496,035	514,844
Restricted equity securities	16,956	16,956
Loans held for sale	2,149	4,616
Financial liabilities:
Deposits	4,084,404	4,009,131
Other borrowings	$ 65,041	$ 122,166

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.

+ References

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-Publisher FASB
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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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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 after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as 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 loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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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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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral.

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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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