Loans - Summary of Aging of Recorded Investment in Past Due Portfolio Loans by Portfolio Class and Category (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans and Leases Receivable, Gross	$ 3,894,770	$ 3,158,161
Non-Covered Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	2,035	999
90 or More Days Past Due	2,119	2,099
Total Past Due	4,154	3,098
Current	3,806,316	3,115,294
Loans and Leases Receivable, Gross	3,810,470	3,118,392
Total	3,811,345	3,119,154
Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	936	334
90 or More Days Past Due	0	171
Total Past Due	936	505
Current	1,794,731	1,632,209
Total	1,795,667	1,632,714
Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	212
90 or More Days Past Due	0	225
Total Past Due	0	437
Current	523,185	349,711
Total	523,185	350,148
Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	205	0
90 or More Days Past Due	0	175
Total Past Due	205	175
Current	711,497	544,633
Total	711,702	544,808
Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	47	355
90 or More Days Past Due	1,489	1,528
Total Past Due	1,536	1,883
Current	281,690	192,659
Total	283,226	194,542
Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	836	91
90 or More Days Past Due	621	0
Total Past Due	1,457	91
Current	344,438	240,669
Total	345,895	240,760
Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	11	7
90 or More Days Past Due	9	0
Total Past Due	20	7
Current	150,775	155,413
Loans and Leases Receivable, Gross	150,795	155,420
Total	$ 151,670	$ 156,182