Loans and Asset Quality Information (Details 5) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012		Mar. 31, 2012
ASSET QUALITY DATA
Nonaccrual loans	$ 90,138	$ 66,525
Foreclosed real estate - non-covered	20,115	26,285		36,838
Foreclosed real estate - covered	30,156	47,290		79,535
Total nonperforming assets	175,369	202,351		252,184
Non-covered nonperforming Assets
ASSET QUALITY DATA
Nonaccrual loans	38,917	33,034		69,665
Restructured loans - accruing	24,378	24,848		10,619
Accruing loans > 90 days past due
Total nonperforming loans	63,295	57,882		80,284
Nonperforming loans held for sale		21,938
Foreclosed real estate - non-covered	20,115	26,285		36,838
Total nonperforming assets	83,410	106,105		117,122
Covered nonperforming Assets
ASSET QUALITY DATA
Nonaccrual loans	51,221	33,491	[1]	42,369
Restructured loans - accruing	10,582	15,465		13,158
Accruing loans > 90 days past due
Total nonperforming loans	61,803	48,956		55,527
Foreclosed real estate - covered	30,156	47,290		79,535
Total nonperforming assets	$ 91,959	$ 96,246		$ 135,062

[1] (1) At March 31, 2013, December 31, 2012, and March 31, 2012, the contractual balance of the nonaccrual loans covered by FDIC loss share agreements was $94.8 million, $64.4 million, and $68.3 million, respectively.