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	$ 13,234	$ 12,374
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	3,000	5,000
Gains on sales of loans	(2,394)	(1,896)
Proceeds from sales of loans	71,205	73,162
Loans originated for sale	(65,996)	(77,528)
Net gains on sales of other real estate and repossessed assets	(235)	(305)
Depreciation of premises and equipment	2,177	1,983
Amortization of intangible assets	1,001	1,067
Gain on sale of investment securities	(847)	0
Net amortization of premiums and discounts on investment securities	863	1,281
Share-based compensation expense	629	314
Contributions to defined benefit pension plan	(15,000)	(12,000)
Net decrease in interest receivable and other assets	7,154	14,426
Net decrease in interest payable and other liabilities	(7,837)	(8,716)
Net cash provided by operating activities	6,954	9,162
Investment securities – available-for-sale:
Proceeds from sales	33,028	0
Proceeds from maturities, calls and principal reductions	41,165	72,992
Purchases	(191,165)	(81,537)
Investment securities – held-to-maturity:
Proceeds from maturities, calls and principal reductions	7,111	8,515
Purchases	(34,940)	(16,599)
Net increase in loans	(24,374)	(21,660)
Proceeds from sales of other real estate and repossessed assets	2,701	4,145
Purchases of premises and equipment and branch bank property, net of disposals	(602)	(2,655)
Net cash used in investing activities	(167,076)	(36,799)
Financing Activities
Net increase in interest- and noninterest-bearing demand deposits and savings accounts	125,946	129,749
Net decrease in time deposits	(40,031)	(35,222)
Net increase in short-term borrowings	37,021	31,296
Repayment of FHLB advances	(34,289)	(937)
Cash dividends paid	(5,791)	(5,503)
Proceeds from directors’ stock plans and exercise of stock options, net of shares withheld	229	240
Shares issued, net of shares withheld, for restricted stock performance units	(372)	(248)
Net cash provided by financing activities	82,713	119,375
Net increase (decrease) in cash and cash equivalents	(77,409)	91,738
Cash and cash equivalents at beginning of period	656,135	381,940
Cash and cash equivalents at end of period	578,726	473,678
Supplemental Disclosure of Cash Flow Information:
Interest paid	4,890	6,577
Loans transferred to other real estate and repossessed assets	2,191	4,299
Closed branch offices transferred to other real estate	382	0
Federal income taxes refunded	$ (3,500)	$ (8,000)