Loans and Allowance for Loan Losses - Past Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	$ 3,244,663	$ 3,166,911
Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	85,752	88,835
Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	6,954	8,101
30-89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	8,549	15,063
90 Days or More and Accruing Interest
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	2,689	1,996
Financing Receivables Current
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	3,140,719	3,052,916
Commercial and Industrial
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	765,115	715,075
Commercial and Industrial | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,951	2,144
Commercial and Industrial | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	910	533
Commercial and Industrial | 30-89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,385	5,859
Commercial and Industrial | 90 Days or More and Accruing Interest
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	619	90
Commercial and Industrial | Financing Receivables Current
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	760,250	706,449
Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	466,495	448,326
Construction | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	7,425	7,728
Construction | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	460	300
Construction | 30-89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	250	1,412
Construction | 90 Days or More and Accruing Interest
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	329	241
Construction | Financing Receivables Current
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	458,031	438,645
Residential Real Estate | 1-to-4 Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	491,725	480,989
Residential Real Estate | 1-to-4 Family Mortgage | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	22,904	23,498
Residential Real Estate | 1-to-4 Family Mortgage | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	2,009	2,548
Residential Real Estate | Residential Line of Credit
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	197,740	194,986
Residential Real Estate | Residential Line of Credit | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	370	699
Residential Real Estate | Multi-Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	63,295	62,374
Residential Real Estate | Multi-Family Mortgage | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	18	20
Residential Real Estate | 30-89 Days Past Due | 1-to-4 Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	3,666	4,678
Residential Real Estate | 30-89 Days Past Due | Residential Line of Credit
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,013	527
Residential Real Estate | 90 Days or More and Accruing Interest | 1-to-4 Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,067	956
Residential Real Estate | 90 Days or More and Accruing Interest | Residential Line of Credit
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	356	134
Residential Real Estate | Financing Receivables Current | 1-to-4 Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	462,079	449,309
Residential Real Estate | Financing Receivables Current | Residential Line of Credit
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	196,001	193,626
Residential Real Estate | Financing Receivables Current | Multi-Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	63,277	62,354
Commercial Real Estate | Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	499,331	495,872
Commercial Real Estate | Owner Occupied | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	11,770	11,962
Commercial Real Estate | Owner Occupied | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,903	2,582
Commercial Real Estate | Non-Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	562,128	551,588
Commercial Real Estate | Non-Owner Occupied | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	18,064	18,164
Commercial Real Estate | Non-Owner Occupied | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,219	1,371
Commercial Real Estate | 30-89 Days Past Due | Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	202	521
Commercial Real Estate | 30-89 Days Past Due | Non-Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	393	121
Commercial Real Estate | 90 Days or More and Accruing Interest | Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans		358
Commercial Real Estate | Financing Receivables Current | Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	485,456	480,449
Commercial Real Estate | Financing Receivables Current | Non-Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	542,452	531,932
Consumer and Other
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	198,834	217,701
Consumer and Other | Purchased Credit Impaired
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	23,620	25,319
Consumer and Other | Non Accruing
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	83	68
Consumer and Other | 30-89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	1,640	1,945
Consumer and Other | 90 Days or More and Accruing Interest
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	318	217
Consumer and Other | Financing Receivables Current
Financing Receivable Recorded Investment Past Due [Line Items]
Loans	$ 173,173	$ 190,152