Loans and Allowance for Loan Losses - Performing and Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 1,840,569	$ 1,777,239
All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,807,701	1,743,081
Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	32,868	34,158
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	888,942	860,027
Commercial Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	871,643	842,345
Commercial Real Estate [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	17,299	17,682
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	410,981	407,254
Consumer Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	402,835	398,542
Consumer Real Estate [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	8,146	8,712
Construction and Land Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	187,009	187,895
Construction and Land Development [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	182,339	183,293
Construction and Land Development [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	4,670	4,602
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	341,471	308,254
Commercial and Industrial [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	339,171	305,697
Commercial and Industrial [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	2,300	2,557
Consumer and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	12,166	13,809
Consumer and Other [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	11,713	13,204
Consumer and Other [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	453	605
Performing [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,805,094	1,739,522
Performing [Member] | Commercial Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	871,007	841,709
Performing [Member] | Consumer Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	401,937	397,306
Performing [Member] | Construction and Land Development [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	181,684	182,746
Performing [Member] | Commercial and Industrial [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	338,806	304,673
Performing [Member] | Consumer and Other [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	11,660	13,088
Impaired Loans [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	2,607	3,559
Impaired Loans [Member] | Commercial Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	636	636
Impaired Loans [Member] | Consumer Real Estate [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	898	1,236
Impaired Loans [Member] | Construction and Land Development [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	655	547
Impaired Loans [Member] | Commercial and Industrial [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	365	1,024
Impaired Loans [Member] | Consumer and Other [Member] | All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 53	$ 116