Purchase Credit Impaired ("PCI") Loans - Summary of Aging of Recorded Investment in Past Due PCI Loans by Portfolio Class and Category (Details) (Covered Loans, USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	$ 854	$ 3,672
90 or More Days Past Due	13,921	10,722
Total Past Due	14,775	14,394
Current	80,013	84,709
Total	94,788	99,103
Commercial & Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	0
90 or More Days Past Due	6	16
Total Past Due	6	16
Current	4,119	3,996
Total	4,125	4,012
Commercial Real Estate Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	0
90 or More Days Past Due	3,115	2,759
Total Past Due	3,115	2,759
Current	17,820	19,936
Total	20,935	22,695
Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	878
90 or More Days Past Due	7,953	6,484
Total Past Due	7,953	7,362
Current	29,571	31,704
Total	37,524	39,066
Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	396	774
90 or More Days Past Due	0	0
Total Past Due	396	774
Current	7,178	6,966
Total	7,574	7,740
Residential Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	448	2,020
90 or More Days Past Due	2,847	1,451
Total Past Due	3,295	3,471
Current	21,019	21,650
Total	24,314	25,121
Consumer & Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	10	0
90 or More Days Past Due	0	12
Total Past Due	10	12
Current	306	457
Total	$ 316	$ 469