Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
OPERATING ACTIVITIES:
Net income	$ 66,814		$ 60,950
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	8,165		15,789
Provision for depreciation and amortization	11,021		11,868
Amortization of investment security premiums, net	11,987		2,713
Investment securities gains, net(A)	(4,040)	[1]	(1,327)	[1]
Net gains on sales of loans held for sale	(358)		(571)
Originations of loans held for sale			(15,789)
Proceeds from sales of loans held for sale	21,699		26,751
Net (increase) decrease in trading securities	(11,300)		2,009
Stock-based compensation	1,407		1,256
(Increase) decrease in interest receivable	3,825		(1,245)
Increase in interest payable	114		69
Increase in income taxes payable	23,496		27,052
Net tax benefit related to equity compensation plans	(649)		(717)
Other changes, net	(12,036)		(26,838)
Net cash provided by operating activities	120,145		101,970
INVESTING ACTIVITIES:
Proceeds from sales of investment securities(A)	6,986	[1]	11,202	[1]
Proceeds from maturities/pay downs of investment securities(A)	643,378	[1]	610,003	[1]
Purchases of investment securities(A)	(558,651)	[1]	(801,432)	[1]
Net (increase) decrease in loans	(81,658)		17,270
Long-term securities purchased under agreements to resell			(350,000)
Repayments of long-term securities purchased under agreements to resell			100,000
Purchases of land, buildings and equipment	(5,393)		(5,819)
Sales of land, buildings and equipment	701		1,686
Net cash provided by (used in) investing activities	5,363		(417,090)
FINANCING ACTIVITIES:
Net increase (decrease) in non-interest bearing, savings, interest checking and money market deposits	(84,876)		334,382
Net increase in time open and C.D.'s	35,703		162,628
Net decrease in short-term federal funds purchased and securities sold under agreements to repurchase	(133,093)		(59,813)
Repayment of long-term borrowings	(297)		(301)
Purchases of treasury stock	(31,600)		(4,311)
Issuance of stock under stock purchase and equity compensation plans	5,954		10,885
Net tax benefit related to equity compensation plans	649		717
Cash dividends paid on common stock	(1,074)		(20,054)
Net cash provided by (used in) financing activities	(208,634)		424,133
Increase (decrease) in cash and cash equivalents	(83,126)		109,013
Cash and cash equivalents at beginning of year	517,551		460,675
Cash and cash equivalents at March 31	434,425		569,688
(A) Available for sale and non-marketable securities
Income tax payments, net	9,271		455
Interest paid on deposits and borrowings	10,115		14,784
Loans transferred to foreclosed real estate	1,311		16,246
Cash dividends payable on common stock at end of period	$ 19,364

[1] Available for sale and non-marketable securities