Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating Activities:
Net income	$ 20,805	$ 22,866
Adjustment to reconcile net income to net cash provided by operating activities:
Provision for credit losses	4,000	10,000
Depreciation and amortization	6,713	6,832
Deferred taxes	(3,002)	0
Amortization of intangibles	743	763
Amortization of debt securities premium and discount, net	3,771	2,820
Share-based compensation expense	530	562
Security gains, net	(19)	(74)
Net deferred loan origination expense	(1,831)	(2,006)
Excess tax benefit from exercise of stock options	12	0
(Increase) decrease in interest receivable	(340)	1,258
Decrease in interest payable	(621)	(992)
Realized gain on mortgages sold	(16,354)	(11,879)
Proceeds from mortgages sold	469,489	376,931
Origination of mortgages held for sale	(425,882)	(395,149)
Loss on other real estate owned, net	1,145	5,762
Increase in bank-owned life insurance	(1,887)	(2,612)
Decrease in prepaid pension asset	1,441	465
Decrease in prepaid deposit insurance assessments	0	5,187
Other, net	(18,781)	(5,175)
Net cash provided by operating activities	39,932	15,559
Investing activities:
Proceeds from calls and maturities of available-for-sale securities	144,157	131,578
Purchases of available-for-sale securities	(337,126)	(164,618)
Net decrease in loans and leases	45,313	100,287
Purchases of premises and equipment	(4,406)	(5,925)
Proceeds from sale of premises and equipment	2,965	906
Proceeds from sale of other real estate owned, net	7,853	10,974
Other, net	0	(8)
Net cash (used in) provided by investing activities	(141,244)	73,194
Financing activities:
Net increase in deposits	76,780	127,133
Net increase (decrease) in short-term debt and other liabilities	(60,872)	27,153
Issuance of common stock	201	108,677
Excess tax benefit from exercise of stock options	(12)	0
Payment of cash dividends	(946)	(944)
Net cash provided by financing activities	15,151	262,019
(Decrease) increase in cash and cash equivalents	(86,161)	350,772
Cash and cash equivalents at beginning of period	1,203,614	499,344
Cash and cash equivalents at end of period	$ 1,117,453	$ 850,116