Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating Activities:
Net income	$ 55,188	$ 61,033
Adjustments to reconcile net income to net cash from operating activities:
Provision for loan losses	6,000	1,100
Deferred tax expense (benefit)	(2,118)	(2,539)
Accretion of loan discounts	(2,900)	(2,962)
Securities premium amortization (discount accretion), net	8,710	4,539
Net (gain) loss on securities transactions	(5)	491
Depreciation and amortization	9,464	9,497
Net loss on sale/write-down of assets/foreclosed assets	3,342	477
Stock-based compensation	2,342	2,555
Net tax benefit (deficiency) from stock-based compensation	(331)	(418)
Excess tax benefits from stock-based compensation	(122)	(41)
Earnings on life insurance policies	(893)	(1,068)
Net change in:
Trading account securities	7,410	(3,237)
Accrued interest receivable and other assets	9,460	41,769
Accrued interest payable and other liabilities	(140,719)	(9,286)
Net cash from operating activities	(45,172)	101,910
Investing Activities:
Securities held to maturity: Purchases	(133,832)
Securities held to maturity: Maturities, calls and principal repayments	8,133	315
Securities available for sale:
Purchases	(4,498,091)	(10,984,308)
Sales	4,498,102	9,985,078
Maturities, calls and principal repayments	321,322	218,136
Net change in loans	47,259	(133,759)
Net cash paid in acquisitions		(7,199)
Proceeds from sales of premises and equipment	12,550	214
Purchases of premises and equipment	(6,834)	(8,276)
Proceeds from sales of repossessed properties	2,142	4,522
Net cash from investing activities	250,751	(925,277)
Financing Activities:
Net change in deposits	(453,462)	152,273
Net change in short-term borrowings	(50,959)	(85,104)
Principal payments on long-term borrowings	(5)	(4)
Proceeds from stock option exercises	20,446	5,542
Excess tax benefits from stock-based compensation	122	41
Proceeds from issuance of preferred stock	144,539
Purchase of treasury stock	(115,200)
Accelerated stock repurchase agreement	(28,800)
Cash dividends paid on common stock	(28,779)	(28,239)
Cash dividends paid on preferred stock
Net cash from financing activities	(512,098)	44,509
Net change in cash and cash equivalents	(306,519)	(778,858)
Cash and equivalents at beginning of period	3,524,979	2,907,592
Cash and equivalents at end of period	$ 3,218,460	$ 2,128,734