Fair Value (Schedule of Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	$ 82,758	$ 71,645	$ 64,145
Due from banks, interest-bearing	326,089	234,348	217,188
Securities available for sale	198,924	199,329	199,156
Securities held to maturity	123,156	129,713	135,808
Total loans, net of allowance	3,405,162	2,686,931	2,626,884
Accrued interest receivable	11,445	9,286	8,785
Bank-owned life insurance	88,081	74,138	73,613
Accrued interest payable	1,143	539	$ 523
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	82,758	71,645
Due from banks, interest-bearing	326,089	234,348
Presold mortgages in process of settlement	17,426	2,116
Accrued interest receivable	11,445	9,286
Bank-owned life insurance	88,081	74,138
Carrying Amount [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Carrying amounts and estimated fair values of financial instruments:
Securities available for sale	198,924	199,329
Securities held to maturity	123,156	129,713
Deposits	3,651,241	2,947,353
Borrowings	397,525	271,394
Accrued interest payable	1,143	539
Carrying Amount [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Carrying amounts and estimated fair values of financial instruments:
Total loans, net of allowance	3,405,162	2,686,931
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	82,758	71,645
Due from banks, interest-bearing	326,089	234,348
Presold mortgages in process of settlement	17,426	2,116
Accrued interest receivable	11,445	9,286
Bank-owned life insurance	88,081	74,138
Fair Value [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Carrying amounts and estimated fair values of financial instruments:
Securities available for sale	198,924	199,329
Securities held to maturity	124,878	130,195
Deposits	3,647,532	2,944,968
Borrowings	388,477	263,255
Accrued interest payable	1,143	539
Fair Value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Carrying amounts and estimated fair values of financial instruments:
Total loans, net of allowance	$ 3,396,635	$ 2,650,820

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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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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 after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as 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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