Fair Value - Carrying Amount and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
ASSETS
Securities available for sale	$ 542,313	$ 516,863
Carrying Amount
ASSETS
Cash and cash equivalents	192,974	45,563
Securities available for sale	542,313	516,863
Trading securities	9,809	7,786
Loans held for sale	930	367
Net loans	2,784,562	2,454,853
FHLB and other equity interests	27,868	24,508
Interest rate swaps	1,877	485
Accrued interest receivable	11,486	10,843
Liabilities
Deposits	(3,102,327)	(2,610,786)
FHLB and other borrowings	(227,907)	(245,117)
Subordinated debentures	(70,620)	(70,620)
Interest rate swaps	(2,362)	(686)
Accrued interest payable	(1,597)	(1,349)
Fair Value
ASSETS
Cash and cash equivalents	192,974	45,563
Securities available for sale	542,313	516,863
Trading securities	9,809	7,786
Loans held for sale	933	368
Net loans	2,765,133	2,433,417
Interest rate swaps	1,877	485
Accrued interest receivable	11,486	10,843
Liabilities
Deposits	(3,106,798)	(2,612,719)
FHLB and other borrowings	(230,679)	(242,592)
Subordinated debentures	(64,084)	(65,794)
Interest rate swaps	(2,362)	(686)
Accrued interest payable	(1,597)	(1,349)
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value
ASSETS
Cash and cash equivalents	192,974	45,563
Securities available for sale	964	934
Trading securities	9,758	7,735
Loans held for sale	0	0
Net loans	0	0
Interest rate swaps	0	0
Accrued interest receivable	6	6
Liabilities
Deposits	(2,674,511)	(2,215,349)
FHLB and other borrowings	0	0
Subordinated debentures	0	0
Interest rate swaps	0	0
Accrued interest payable	0	0
Significant Other Observable Inputs (Level 2) \| Fair Value
ASSETS
Cash and cash equivalents	0	0
Securities available for sale	538,554	515,929
Trading securities	51	51
Loans held for sale	933	368
Net loans	0	0
Interest rate swaps	1,877	485
Accrued interest receivable	3,238	3,368
Liabilities
Deposits	(432,287)	(397,370)
FHLB and other borrowings	(230,679)	(242,592)
Subordinated debentures	(64,084)	(65,794)
Interest rate swaps	(2,362)	(686)
Accrued interest payable	(1,597)	(1,349)
Significant Unobservable Inputs (Level 3) \| Fair Value
ASSETS
Cash and cash equivalents	0	0
Securities available for sale	2,795	0
Trading securities	0	0
Loans held for sale	0	0
Net loans	2,765,133	2,433,417
Interest rate swaps	0	0
Accrued interest receivable	8,242	7,469
Liabilities
Deposits	0	0
FHLB and other borrowings	0	0
Subordinated debentures	0	0
Interest rate swaps	0	0
Accrued interest payable	$ 0	$ 0

Federal Home Loan Bank, and Other Restricted Equity Interests

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Fair value portion of amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties.

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Fair value portion of accrued expenses.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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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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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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