Fair Value of Financial Instruments (Schedule of Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	$ 114,301	$ 71,645
Securities available for sale	343,270	199,329
Securities held to maturity	118,503	129,713
Total loans, net of allowance	4,019,071	2,686,931
Accrued interest receivable	14,094	9,286
FDIC Indemnification Asset			$ 8,439	$ 22,569
Bank-owned life insurance	99,162	74,138
Accrued interest payable	1,235	539
Level in Fair Value Hierachy [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	1	1
Due from banks, interest-bearing	1	1
Securities available for sale	2	2
Securities held to maturity	2	2
Presold mortgages in process of settlement	1	1
Total loans, net of allowance	3	3
Accrued interest receivable	1	1
Bank-owned life insurance	1	1
Deposits	2	2
Borrowings	2	2
Accrued interest payable	2	2
Carrying Amount [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	114,301	71,645
Due from banks, interest-bearing	375,189	234,348
Securities available for sale	343,270	199,329
Securities held to maturity	118,503	129,713
Presold mortgages in process of settlement	12,459	2,116
Total loans, net of allowance	4,019,071	2,686,931
Accrued interest receivable	14,094	9,286
Bank-owned life insurance	99,162	74,138
Deposits	4,406,955	2,947,353
Borrowings	407,543	271,394
Accrued interest payable	1,235	539
Fair Value [Member]
Carrying amounts and estimated fair values of financial instruments:
Cash and due from banks, noninterest-bearing	114,301	71,645
Due from banks, interest-bearing	375,189	234,348
Securities available for sale	343,270	199,329
Securities held to maturity	118,998	130,195
Presold mortgages in process of settlement	12,459	2,116
Total loans, net of allowance	4,010,551	2,650,820
Accrued interest receivable	14,094	9,286
Bank-owned life insurance	99,162	74,138
Deposits	4,401,757	2,944,968
Borrowings	397,903	263,255
Accrued interest payable	$ 1,235	$ 539

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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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A bank's noninterest bearing demand deposits in other banks (such as correspondents).

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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.

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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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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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