Changes in Noncovered Other Real Estate Owned (Summary of Noncovered Other Real Estate Owned) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Other Real Estate Owned [Line Items]
Balance, beginning of period	$ 51,019
Proceeds from sale of OREO property	(7,829)	(5,372)
Gain (loss) on sale of OREO	2,954	2,712
Total OREO, end of period	41,174
Noncovered Loans [Member]
Other Real Estate Owned [Line Items]
Balance, beginning of period	22,893	30,991
Transfers in, net of write-downs ($118 and 91, respectively)	3,803	2,042
Transfers in, write-downs	118	91
OREO improvements	11	251
Additional OREO write-down	(1,722)	(1,910)
Proceeds from sale of OREO property	(7,829)	(5,372)
Gain (loss) on sale of OREO	(412)	79
Total OREO, end of period	$ 16,744	$ 26,081