Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 25,503	$ 13,467
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of investment premiums, net	10,744	9,111
Gain on sale of investment securities, net	(148)
Other-than-temporary impairment on investment securities held to maturity		25
(Gain) loss on sale of non-covered other real estate owned	(336)	703
Gain on sale of covered other real estate owned	(452)	(305)
Valuation adjustment on non-covered other real estate owned	3,523	2,130
Valuation adjustment on covered other real estate owned	2,906	1,256
Provision for non-covered loan and lease losses	3,167	15,030
Provision for covered loan and lease losses	(31)	7,268
Change in FDIC indemnification asset	1,845	(2,905)
Depreciation, amortization and accretion	4,020	3,031
Increase in mortgage servicing rights	(2,948)	(1,334)
Change in mortgage servicing rights carried at fair value	922	183
Change in junior subordinated debentures carried at fair value	548	532
Stock-based compensation	916	1,119
Net (increase) decrease in trading account assets	(847)	452
(Gain) loss on sale of loans	(6,094)	815
Origination of loans held for sale	(352,522)	(139,229)
Proceeds from sales of loans held for sale	330,190	161,385
Excess tax benefits from the exercise of stock options	(46)	(3)
Change in other assets and liabilities:
Net decrease in other assets	15,493	137
Net (decrease) increase in other liabilities	(5,554)	600
Net cash provided by operating activities	30,799	73,468
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investment securities available for sale	(266,541)	(521,254)
Proceeds from investment securities available for sale	331,374	146,918
Proceeds from investment securities held to maturity	170	186
Redemption of restricted equity securities	128	180
Net non-covered loan and lease originations	(68,883)	(6,455)
Net covered loan and lease paydowns	23,956	33,964
Proceeds from sales of loans	4,428	5,392
Proceeds from disposals of furniture and equipment	653	115
Purchases of premises and equipment	(5,863)	(7,926)
Net proceeds from FDIC indemnification asset	12,649	33,862
Proceeds from sales of non-covered other real estate owned	3,892	5,349
Proceeds from sales of covered other real estate owned	5,033	4,259
Net cash provided (used) by investing activities	40,996	(305,410)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net decrease in deposit liabilities	(121,444)	(140,870)
Net increase in securities sold under agreements to repurchase	2,040	19,666
Repayment of term debt		(5,000)
Dividends paid on common stock	(7,890)	(5,743)
Excess tax benefits from stock based compensation	46	3
Proceeds from stock options exercised	21	212
Retirement of common stock	(5,013)	(488)
Net cash used by financing activities	(132,240)	(132,220)
Net decrease in cash and cash equivalents	(60,445)	(364,162)
Cash and cash equivalents, beginning of period	598,766	1,004,125
Cash and cash equivalents, end of period	538,321	639,963
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Interest	14,392	21,623
Income taxes		70
SUPPLEMENTAL DISCLOSURE OF NONCASH INVESTING AND FINANCING ACTIVITIES:
Change in unrealized gains on investment securities available for sale, net of taxes	1,124	489
Change in unrealized losses on investment securities held to maturity related to factors other than credit, net of taxes	41	49
Cash dividend declared on common and preferred stock and payable after period-end	7,887	5,761
Transfer of non-covered loans to non-covered other real estate owned	7,209	9,903
Transfer of covered loans to covered other real estate owned	784	3,036
Transfer of covered loans to non-covered loans	4,563
Transfer from FDIC indemnification asset to due from FDIC and other	$ 10,827	$ 17,445