Other Real Estate Owned (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
OREO activity
Balance, beginning of period	$ 79,303,000	$ 129,340,000
Additions	9,675,000	8,292,000
Sales	(22,174,000)	(21,239,000)
Valuation adjustments	(3,267,000)	(8,863,000)
Balance, end of period	63,537,000	107,530,000
OREO Valuation Allowances	28,700,000		33,600,000
Non-Covered OREO
OREO activity
Balance, beginning of period	21,027,000	30,790,000
Additions	382,000	2,217,000
Sales	(1,391,000)	(2,877,000)
Valuation adjustments	(232,000)	(1,056,000)
Balance, end of period	19,786,000	29,074,000
Covered OREO
OREO activity
Balance, beginning of period	58,276,000	98,550,000
Additions	9,293,000	6,075,000
Sales	(20,783,000)	(18,362,000)
Valuation adjustments	(3,035,000)	(7,807,000)
Balance, end of period	$ 43,751,000	$ 78,456,000
FDIC reimbursement (as a percent)	80.00%
Payable to FDIC (as a percent)	80.00%