Covered Assets and FDIC Loss-sharing Asset (Analysis and Allowance for Losses on Covered Loans) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
Covered Loans	$ 846,835	$ 714,733
Allowance For Losses On Covered Loans	7,948	6,055
Valuation discount resulting from acquisition accounting	231,577	191,617
Covered loans, net	607,310	517,061
Commercial Business [Member]
Covered Loans	241,391	165,255
Weighted-Average Risk Rating	5.82%	5.74%
Allowance For Losses On Covered Loans	3,156	2,903
Real Estate 1-4 Family [Member]
Covered Loans	84,568	68,700
Weighted-Average Risk Rating	4.68%	4.77%
Allowance For Losses On Covered Loans	508	1,013
Real Estate Commercial & Multifamily [Member]
Covered Loans	365,099	341,063
Weighted-Average Risk Rating	5.72%	5.70%
Allowance For Losses On Covered Loans	3,861	821
Construction 1-4 Family [Member]
Covered Loans	57,638	39,754
Weighted-Average Risk Rating	7.44%	7.29%
Allowance For Losses On Covered Loans	0	98
Construction Commercial & Multifamily [Member]
Covered Loans	32,203	41,624
Weighted-Average Risk Rating	6.65%	6.79%
Allowance For Losses On Covered Loans	382	469
Consumer [Member]
Covered Loans	65,936	58,337
Weighted-Average Risk Rating	4.60%	4.49%
Allowance For Losses On Covered Loans	$ 41	$ 751