Purchase Credit Impaired ("PCI") Loans - Summary of PCI Loans by Category (Details) (Covered Loans, USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Covered Loans [Line Items]
Recorded Investment PCI Loans	$ 94,788	$ 99,103
Construction and Land Development
Covered Loans [Line Items]
Weighted- Average Risk Rating	6.26	6.16
Recorded Investment PCI Loans	7,574	7,740
Commercial Real Estate Investor Owned
Covered Loans [Line Items]
Weighted- Average Risk Rating	7.12	7.07
Recorded Investment PCI Loans	37,524	39,066
Commercial Real Estate Owner Occupied
Covered Loans [Line Items]
Weighted- Average Risk Rating	6.39	6.35
Recorded Investment PCI Loans	20,935	22,695
Residential Real Estate
Covered Loans [Line Items]
Weighted- Average Risk Rating	5.52	5.54
Recorded Investment PCI Loans	24,314	25,121
Total real estate loans
Covered Loans [Line Items]
Recorded Investment PCI Loans	90,347	94,622
Commercial & Industrial
Covered Loans [Line Items]
Weighted- Average Risk Rating	6.67	6.57
Recorded Investment PCI Loans	4,125	4,012
Consumer and other
Covered Loans [Line Items]
Weighted- Average Risk Rating	5.29	5.39
Recorded Investment PCI Loans	$ 316	$ 469