Noninterest Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Noninterest Expense [Abstract]
Employee compensation and benefits	$ 46,485	$ 41,836	$ 93,866	$ 85,686
OREO operations	3,337	14,452	5,329	25,852
Occupancy and equipment	10,932	10,156	21,219	19,978
Data processing	7,033	6,608	13,463	12,688
FDIC insurance	1,989	3,439	3,846	7,393
Professional Fees	4,800	3,352	7,789	6,410
Depreciation	2,923	3,014	5,836	6,026
Advertising	3,774	2,768	6,928	4,727
Travel and entertainment	1,535	1,359	2,599	2,595
Merger and acquisition	2,262	0	8,397	0
Amortization of other intangible assets	1,791	1,224	3,196	2,449
Other	746	3,379	3,788	6,091
Total noninterest expense	$ 87,607	$ 91,587	$ 176,256	$ 179,895