Other Real Estate Owned (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
OREO activity
Balance, beginning of year	$ 162,541,000	$ 153,292,000	$ 178,183,000	$ 113,866,000
Additions	16,918,000	45,981,000	88,573,000	131,170,000
Sales	(23,698,000)	(21,528,000)	(83,998,000)	(39,908,000)
Valuation adjustments	(8,392,000)	(8,892,000)	(35,389,000)	(36,275,000)
Balance, end of year	147,369,000	168,853,000	147,369,000	168,853,000
OREO Valuation Allowances	40,600,000	3,200,000	40,600,000	3,200,000	5,500,000
Non-Covered OREO
OREO activity
Balance, beginning of year	47,634,000	54,451,000	57,317,000	53,308,000
Additions	1,647,000	19,595,000	12,175,000	46,740,000
Sales	(3,894,000)	(14,108,000)	(21,041,000)	(21,696,000)
Valuation adjustments	(866,000)	(1,476,000)	(3,930,000)	(19,890,000)
Balance, end of year	44,521,000	58,462,000	44,521,000	58,462,000
Covered OREO
OREO activity
Balance, beginning of year	114,907,000	98,841,000	120,866,000	60,558,000
Additions	15,271,000	26,386,000	76,398,000	84,430,000
Sales	(19,804,000)	(7,420,000)	(62,957,000)	(18,212,000)
Valuation adjustments	(7,526,000)	(7,416,000)	(31,459,000)	(16,385,000)
Balance, end of year	$ 102,848,000	$ 110,391,000	$ 102,848,000	$ 110,391,000
FDIC reimbursement (as a percent)			80.00%