Portfolio Loans Covered by Loss Share (Covered loans) - Summary of Covered Loans by Category (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Covered Loans	Dec. 31, 2012 Covered Loans	Jun. 30, 2013 Covered Loans Real Estate Loans	Dec. 31, 2012 Covered Loans Real Estate Loans	Jun. 30, 2013 Covered Loans Real Estate Loans Construction and Land Development rating	Dec. 31, 2012 Covered Loans Real Estate Loans Construction and Land Development rating	Jun. 30, 2013 Covered Loans Real Estate Loans Commercial Real Estate Investor Owned rating	Dec. 31, 2012 Covered Loans Real Estate Loans Commercial Real Estate Investor Owned rating	Jun. 30, 2013 Covered Loans Real Estate Loans Commercial Real Estate Owner Occupied rating	Dec. 31, 2012 Covered Loans Real Estate Loans Commercial Real Estate Owner Occupied rating	Jun. 30, 2013 Covered Loans Real Estate Loans Residential Real Estate rating	Dec. 31, 2012 Covered Loans Real Estate Loans Residential Real Estate rating	Jun. 30, 2013 Covered Loans Commercial and industrial rating	Dec. 31, 2012 Covered Loans Commercial and industrial rating	Jun. 30, 2013 Covered Loans Consumer & other rating	Dec. 31, 2012 Covered Loans Consumer & other rating
Covered Loans [Line Items]
Net cash proceeds received from FDIC loss share receivable	$ 7,442	$ 70,014
Weighted-Average Risk Rating							7.08	7.06	6.50	6.08	6.66	6.65	5.70	5.68	6.76	6.57	4.06	4.19
Recorded Investment Covered Loans			$ 169,863	$ 201,118	$ 157,293	$ 177,810	$ 21,122	$ 30,537	$ 54,087	$ 57,602	$ 43,686	$ 47,140	$ 38,398	$ 42,531	$ 11,484	$ 22,034	$ 1,086	$ 1,274