Carrying Amount and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Carrying (Reported) Amount, Fair Value Disclosure
Assets
Cash and cash equivalents	$ 76,307	$ 51,787
Securities available for sale	165,579	366,173
Securities held to maturity	47,133	72,541
Loans held for investment, net of allowance	1,835,000	1,686,308
FDIC indemnification asset	12,173	20,844
Interest receivable	5,553	6,007
Deferred compensation assets	3,224	3,464
Liabilities
Securities sold under agreements to repurchase	98,005	138,614
Interest payable	1,280	1,260
FHLB and other borrowings	80,708	80,756
Derivative financial liabilities	167	251
Deferred compensation liabilities	3,224	3,464
Carrying (Reported) Amount, Fair Value Disclosure \| Demand Deposits
Liabilities
Deposits Fair Value	427,705	451,511
Carrying (Reported) Amount, Fair Value Disclosure \| Interest-bearing Deposits
Liabilities
Deposits Fair Value	378,339	347,705
Carrying (Reported) Amount, Fair Value Disclosure \| Savings Deposits
Liabilities
Deposits Fair Value	523,260	530,585
Carrying (Reported) Amount, Fair Value Disclosure \| Bank Time Deposits
Liabilities
Deposits Fair Value	512,034	543,458
Estimate of Fair Value, Fair Value Disclosure
Assets
Cash and cash equivalents	76,307	51,787
Securities available for sale	165,579	366,173
Securities held to maturity	47,266	72,490
Loans held for investment, net of allowance	1,805,999	1,685,061
FDIC indemnification asset	8,112	10,753
Interest receivable	5,553	6,007
Deferred compensation assets	3,224	3,464
Liabilities
Securities sold under agreements to repurchase	98,879	140,880
Interest payable	1,280	1,260
FHLB and other borrowings	83,551	85,774
Derivative financial liabilities	167	251
Deferred compensation liabilities	3,224	3,464
Estimate of Fair Value, Fair Value Disclosure \| Demand Deposits
Liabilities
Deposits Fair Value	427,705	451,511
Estimate of Fair Value, Fair Value Disclosure \| Interest-bearing Deposits
Liabilities
Deposits Fair Value	378,339	347,705
Estimate of Fair Value, Fair Value Disclosure \| Savings Deposits
Liabilities
Deposits Fair Value	523,260	530,585
Estimate of Fair Value, Fair Value Disclosure \| Bank Time Deposits
Liabilities
Deposits Fair Value	507,917	541,059
Securities available for sale	165,579	366,173
Securities held to maturity	47,266	72,490
FDIC indemnification asset	12,173	20,844	$ 27,900
Interest receivable	5,553	6,007
Derivative financial liabilities	167	251
Level 1
Assets
Cash and cash equivalents	76,307	51,787
Securities available for sale	55	54
Deferred compensation assets	3,224	3,464
Liabilities
Deferred compensation liabilities	3,224	3,464
Level 2
Assets
Securities available for sale	165,524	366,119
Securities held to maturity	47,266	72,490
Loans held for investment, net of allowance	4,701	4,886
Interest receivable	5,553	6,007
Liabilities
Securities sold under agreements to repurchase	98,879	140,880
Interest payable	1,280	1,260
FHLB and other borrowings	83,551	85,774
Derivative financial liabilities	167	251
Level 2 \| Demand Deposits
Liabilities
Deposits Fair Value	427,705	451,511
Level 2 \| Interest-bearing Deposits
Liabilities
Deposits Fair Value	378,339	347,705
Level 2 \| Savings Deposits
Liabilities
Deposits Fair Value	523,260	530,585
Level 2 \| Bank Time Deposits
Liabilities
Deposits Fair Value	507,917	541,059
Level 3
Assets
Loans held for investment, net of allowance	1,801,298	1,680,175
FDIC indemnification asset	$ 8,112	$ 10,753

Deferred compensation assets fair value.

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Deferred compensation liabilities fair value.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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 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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No definition available.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

+ References

No definition available.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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