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	$ 46,508	$ 40,784
Adjustments to net income:
Provision for losses on covered loans	7,466	19,116
Amortization of intangibles	1,886	2,168
Depreciation and amortization	7,428	6,748
Share-based employee compensation expense	4,706	4,678
Deferred income tax benefit	297	(811)
Gain on disposal of assets	(2,191)	(2,424)
Gain on sale of securities	(449)	(130)
Impairment loss on securities		164
Other, net	(2,430)	(12,700)
Net change in:
Trading securities	(20,559)	174,171
Other assets and other liabilities, net	(41,395)	35,560
Net cash provided by operating activities	1,267	267,324
Cash Flows From Investing Activities
Purchase of securities available-for-sale	(629,049)	(598,336)
Sales of securities available-for-sale	5,173	6,094
Maturities and paydowns of securities available-for-sale	1,362,442	436,519
Purchase of securities held-to-maturity	(530,159)
Maturities and paydowns of securities held-to-maturity	1,005
Loan originations, net of principal collections	(346,887)	199,409
Net payments for premises and equipment	(7,025)	(9,567)
Net cash (paid) acquired in acquisitions	(850)	7,922
Other investing activities, net	20,592	16,624
Net cash (used in) provided by investing activities	(124,758)	58,665
Cash Flows From Financing Activities
Net increase in deposits	400,155	292,671
Net decrease in federal funds purchased and securities sold under repurchase agreements	(40,000)
Net (decrease) increase in short-term borrowings, net of transfers from long-term debt	(1,500)	70
Proceeds from exercise of stock options	2,000	4,015
Tax benefit from exercise of stock options	770	920
Cash dividends paid	(13,302)	(10,576)
Other financing activities, net	(1,272)	(609)
Net cash provided by financing activities	346,851	286,491
Net increase in cash and cash equivalents	223,360	612,480
Cash and cash equivalents at beginning of year	244,814	434,689
Cash and cash equivalents at end of period	468,174	1,047,169
Cash paid during the period for:
Interest	22,386	32,666
Income taxes	27,163	2
Non-cash investing activities:
Transfer of loans to other real estate owned	8,292	34,139
Transfer of SERP liability to equity	$ 8,348