Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012
OPERATING ACTIVITIES:
Net income	$ 195,292		$ 204,836
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	14,810		18,961
Provision for depreciation and amortization	31,152		32,565
Amortization of investment security premiums, net	22,840		29,989
Investment securities gains (losses), net	3,083	[1]	(8,556)	[1]
Net gains on sales of loans held for sale	0		(376)
Proceeds from sales of loans held for sale	0		22,649
Net decrease in trading securities	15,977		5,454
Stock-based compensation	4,605		3,705
(Increase) decrease in interest receivable	2,694		4,728
Increase (decrease) in interest payable	(1,319)		(1,067)
Increase (decrease) in income taxes payable	7,183		(5,571)
Net tax benefit related to equity compensation plans	(454)		(1,233)
Other changes, net	(7,086)		(10,718)
Net cash provided by (used in) operating activities	288,777		295,366
INVESTING ACTIVITIES:
Cash received in acquisition	47,643		0
Proceeds from sales of investment securities	6,624	[1]	14,931	[1]
Proceeds from maturities/pay downs of investment securities	2,047,277	[1]	2,341,083	[1]
Purchases of investment securities	(1,522,765)	[1]	(2,036,260)	[1]
Net (increase) decrease in loans	(796,215)		(489,628)
Long-term securities purchased under agreements to resell	(125,000)		(125,000)
Repayments of long-term securities purchased under agreements to resell	175,000		125,000
Purchases of land, buildings and equipment	(18,731)		(19,243)
Sales of land, buildings and equipment	723		2,338
Net cash provided by (used in) investing activities	(185,444)		(186,779)
FINANCING ACTIVITIES:
Net increase (decrease) in non-interest bearing, savings, interest checking and money market deposits	(569,342)		554,167
Net increase (decrease) in time open and C.D.'s	81,449		(479,383)
Net increase in short-term federal funds purchased and securities sold under agreements to repurchase	726,843		1,868
Repayment of long-term borrowings	(50,961)		(8,073)
Purchases of treasury stock	(69,195)		(75,536)
Issuance of stock under stock purchase and equity compensation plans	8,154		9,766
Net tax benefit related to equity compensation plans	454		1,233
Cash dividends paid on common stock	(61,536)		(60,819)
Net cash provided by (used in) financing activities	65,866		(56,777)
Increase (decrease) in cash and cash equivalents	169,199		51,810
Cash and cash equivalents at beginning of year	779,825		517,551
Cash and cash equivalents at September 30	949,024		569,361
Supplemental Cash Flow Information:
Income tax payments, net	84,331		104,175
Interest paid on deposits and borrowings	24,956		30,198
Loans transferred to foreclosed real estate	6,744		7,178
Loans transferred from held for sale to held for investment category	$ 8,941		$ 0

[1] Available for sale and non-marketable securities