Fair Value (Schedule of Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	$ 97,163	$ 114,301	$ 80,234
Due from banks, interest-bearing	462,972	375,189	337,326
Securities available for sale	334,068	343,270	207,496
Securities held to maturity	108,265	118,503	127,866
Total loans, net of allowance	4,126,092	4,019,071	3,351,951
Accrued interest receivable	13,930	14,094	10,830
Bank-owned life insurance	100,413	99,162	87,501
Accrued interest payable	1,651	1,235	$ 1,014
Carrying Amount [Member] \| Quoted Prices in Markets for Identical Assets (Level 1) [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	97,163	114,301
Due from banks, interest-bearing	462,972	375,189
Presold mortgages in process of settlement	9,311	12,459
Accrued interest receivable	13,930	14,094
Bank-owned life insurance	100,413	99,162
Carrying Amount [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Carrying amounts and estimated fair values of financial instruments:
Securities available for sale	334,068	343,270
Securities held to maturity	108,265	118,503
Deposits	4,553,621	4,406,955
Borrowings	407,076	407,543
Accrued interest payable	1,651	1,235
Carrying Amount [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Carrying amounts and estimated fair values of financial instruments:
Total loans, net of allowance	4,126,092	4,019,071
Fair Value [Member] \| Quoted Prices in Markets for Identical Assets (Level 1) [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	97,163	114,301
Due from banks, interest-bearing	462,972	375,189
Presold mortgages in process of settlement	9,311	12,459
Accrued interest receivable	13,930	14,094
Bank-owned life insurance	100,413	99,162
Fair Value [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Carrying amounts and estimated fair values of financial instruments:
Securities available for sale	334,068	343,270
Securities held to maturity	107,068	118,998
Deposits	4,547,235	4,401,757
Borrowings	398,113	397,903
Accrued interest payable	1,651	1,235
Fair Value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Carrying amounts and estimated fair values of financial instruments:
Total loans, net of allowance	$ 4,084,898	$ 4,010,551

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure.

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

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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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 debt instrument payable, including, but not limited to, notes payable and loans payable.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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 investment in debt security measured at amortized cost (held-to-maturity).

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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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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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums over and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans and leases covered under loss sharing agreements.

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