Covered Assets and FDIC Loss-sharing Asset (Covered OREO at Carrying Value) (Details) (Covered OREO [Member], USD $) In Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011
Covered OREO [Member]
Balance, beginning of period	$ 23,730	$ 14,443
Established through acquisitions	0	10,387
Transfers in, net of write-downs ($23 for Q3 2011 and $441 for Q3 2011YTD)	2,979	8,071
OREO improvements	0	0
Additional OREO write-downs	189	302
Proceeds from sale of OREO property	(3,523)	(14,604)
Gain on sale of covered oreo	1,838	6,840
Balance, end of period	$ 24,835	$ 24,835