Loans and Leases - Credit Quality Indicators (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	$ 3,835,228	$ 3,629,198
Total Loans and Leases Held for Investment, Acquired	332,676	377,376
Grade: 1. Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	3,035,157	2,851,733
Total Loans and Leases Held for Investment, Acquired	265,973	304,928
Grade: 2. Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	48,446	55,799
Total Loans and Leases Held for Investment, Acquired	0	0
Grade: 3. Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	32,719	31,119
Total Loans and Leases Held for Investment, Acquired	13,100	13,619
Grade: 4. Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	0	0
Total Loans and Leases Held for Investment, Acquired	0	0
Internally Assigned Grades [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	3,116,322	2,938,651
Total Loans and Leases Held for Investment, Acquired	279,073	318,547
Performing Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	717,083	689,112
Total Loans and Leases Held for Investment, Acquired	51,616	56,867
Nonperforming Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,823	1,435
Total Loans and Leases Held for Investment, Acquired	1,987	1,962
Performing and Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	718,906	690,547
Total Loans and Leases Held for Investment, Acquired	53,603	58,829
Commercial, Financial and Agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	921,182	913,166
Total Loans and Leases Held for Investment, Acquired	15,967	24,519
Commercial, Financial and Agricultural [Member] | Grade: 1. Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	874,098	882,736
Total Loans and Leases Held for Investment, Acquired	15,967	24,450
Commercial, Financial and Agricultural [Member] | Grade: 2. Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	27,036	23,287
Total Loans and Leases Held for Investment, Acquired	0	0
Commercial, Financial and Agricultural [Member] | Grade: 3. Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	20,048	7,143
Total Loans and Leases Held for Investment, Acquired	0	69
Commercial, Financial and Agricultural [Member] | Grade: 4. Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	0	0
Total Loans and Leases Held for Investment, Acquired	0	0
Commercial, Financial and Agricultural [Member] | Internally Assigned Grades [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	921,182	913,166
Total Loans and Leases Held for Investment, Acquired	15,967	24,519
Real Estate-Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,650,052	1,507,579
Total Loans and Leases Held for Investment, Acquired	212,095	233,625
Real Estate-Commercial [Member] | Grade: 1. Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,622,980	1,455,234
Total Loans and Leases Held for Investment, Acquired	199,560	220,911
Real Estate-Commercial [Member] | Grade: 2. Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	17,773	31,791
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Commercial [Member] | Grade: 3. Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	9,299	20,554
Total Loans and Leases Held for Investment, Acquired	12,535	12,714
Real Estate-Commercial [Member] | Grade: 4. Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	0	0
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Commercial [Member] | Internally Assigned Grades [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,650,052	1,507,579
Total Loans and Leases Held for Investment, Acquired	212,095	233,625
Real Estate-Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	230,459	215,513
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Construction [Member] | Grade: 1. Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	228,421	215,407
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Construction [Member] | Grade: 2. Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,932	0
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Construction [Member] | Grade: 3. Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	106	106
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Construction [Member] | Grade: 4. Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	0	0
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Construction [Member] | Internally Assigned Grades [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	230,459	215,513
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Residential Secured for Business Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	314,629	302,393
Total Loans and Leases Held for Investment, Acquired	51,011	60,403
Real Estate-Residential Secured for Business Purpose [Member] | Grade: 1. Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	309,658	298,356
Total Loans and Leases Held for Investment, Acquired	50,446	59,567
Real Estate-Residential Secured for Business Purpose [Member] | Grade: 2. Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,705	721
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Residential Secured for Business Purpose [Member] | Grade: 3. Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	3,266	3,316
Total Loans and Leases Held for Investment, Acquired	565	836
Real Estate-Residential Secured for Business Purpose [Member] | Grade: 4. Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	0	0
Total Loans and Leases Held for Investment, Acquired	0	0
Real Estate-Residential Secured for Business Purpose [Member] | Internally Assigned Grades [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	314,629	302,393
Total Loans and Leases Held for Investment, Acquired	51,011	60,403
Real Estate Residential Secured For Personal Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	373,792	338,451
Total Loans and Leases Held for Investment, Acquired	46,017	49,959
Real Estate Residential Secured For Personal Purpose [Member] | Performing Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	372,578	337,762
Total Loans and Leases Held for Investment, Acquired	45,064	49,061
Real Estate Residential Secured For Personal Purpose [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	1,214	689
Total Loans and Leases Held for Investment, Acquired	953	898
Real Estate Residential Secured For Personal Purpose [Member] | Performing and Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	373,792	338,451
Total Loans and Leases Held for Investment, Acquired	46,017	49,959
Real Estate-Home Equity Secured for Personal Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	170,482	177,523
Total Loans and Leases Held for Investment, Acquired	7,446	8,728
Real Estate-Home Equity Secured for Personal Purpose [Member] | Performing Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	170,172	177,139
Total Loans and Leases Held for Investment, Acquired	6,412	7,664
Real Estate-Home Equity Secured for Personal Purpose [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	310	384
Total Loans and Leases Held for Investment, Acquired	1,034	1,064
Real Estate-Home Equity Secured for Personal Purpose [Member] | Performing and Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	170,482	177,523
Total Loans and Leases Held for Investment, Acquired	7,446	8,728
Loans to Individuals [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	32,345	32,617
Total Loans and Leases Held for Investment, Acquired	140	142
Loans to Individuals [Member] | Performing Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	32,216	32,562
Total Loans and Leases Held for Investment, Acquired	140	142
Loans to Individuals [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	129	55
Total Loans and Leases Held for Investment, Acquired	0	0
Loans to Individuals [Member] | Performing and Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	32,345	32,617
Total Loans and Leases Held for Investment, Acquired	140	142
Lease Financings [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	142,287	141,956
Total Loans and Leases Held for Investment, Acquired	0	0
Lease Financings [Member] | Performing Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	142,117	141,649
Total Loans and Leases Held for Investment, Acquired	0	0
Lease Financings [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	170	307
Total Loans and Leases Held for Investment, Acquired	0	0
Lease Financings [Member] | Performing and Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases Held for Investment, Originated	142,287	141,956
Total Loans and Leases Held for Investment, Acquired	$ 0	$ 0