Consolidated Statements Of Cash Flows (USD $)	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Operating Activities
Net income	$ 31,759,000	$ 19,862,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan and covered loan losses	44,739,000	68,671,000
Depreciation of premises, furniture, and equipment	4,655,000	4,257,000
Net amortization of premium on securities	7,300,000	5,154,000
Net losses (gains) on sale of securities	185,000	(1,037,000)
Net losses on sale of other real estate owned	3,050,000	1,922,000
Net amortization (accretion) of discount on covered assets	1,179,000	(2,298,000)
Bank owned life insurance income	(785,000)	(775,000)
Net increase (decrease) in deferred loan fees	870,000	(1,095,000)
Share-based compensation expense	9,809,000	5,817,000
Provision for deferred income tax expense	6,361,000	2,579,000
Amortization of other intangibles	1,338,000	751,000
Net (increase) decrease in loans held-for-sale	(3,293,000)	17,255,000
Fair market value adjustments on derivatives	696,000	(178,000)
Net (increase) decrease in accrued interest receivable	(1,357,000)	1,726,000
Net increase (decrease) in accrued interest payable	288,000	(201,000)
Net decrease in other assets	1,304,000	14,366,000
Net decrease in other liabilities	(29,670,000)	(12,624,000)
Net cash provided by operating activities	78,428,000	124,152,000
Investing Activities
Proceeds from maturities, repayments, and calls	224,861,000	188,209,000
Proceeds from sales	812,000	60,493,000
Purchases	(74,724,000)	(404,493,000)
Held-to-maturity securities:
Proceeds from maturities, repayments, and calls	26,791,000
Purchases	(231,316,000)
Net (increase) decrease in loans	(512,184,000)	285,017,000
Net decrease in covered assets	56,939,000	54,386,000
Proceeds from sale of other real estate owned	22,595,000	25,892,000
Net purchases of premises, furniture, and equipment	(4,199,000)	(1,453,000)
Net cash (used in) provided by investing activities	(490,425,000)	208,051,000
Financing Activities
Net increase (decrease) in deposit accounts	341,676,000	(301,161,000)
Net decrease in short-term borrowings, excluding FHLB advances		(941,000)
Net increase (decrease) in FHLB advances	174,000,000	(59,000,000)
Payments for the issuance of common stock		(9,000)
Stock repurchased in connection with benefit plans	(1,185,000)	(561,000)
Cash dividends paid	(7,568,000)	(7,515,000)
Proceeds from exercise of stock options and issuance of common stock under benefit plans	274,000	1,012,000
Shortfall tax benefit from exercise of stock options and vesting of restricted shares		(405,000)
Net cash provided by (used in) financing activities	507,197,000	(368,580,000)
Net increase (decrease) in cash and cash equivalents	95,200,000	(36,377,000)
Cash and cash equivalents at beginning of year	361,741,000	654,088,000
Cash and cash equivalents at end of period	456,941,000	617,711,000
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	31,806,000	39,749,000
Cash paid for income taxes	30,519,000	13,317,000
Non-cash transfers of loans to other real estate	$ 23,481,000	$ 73,328,000