CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Operating activities:
Net income	$ 41,242	$ 37,287
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan and lease losses	1,631	4,959
Depreciation of premises and equipment	3,515	3,151
Depreciation of equipment owned and leased to others	9,745	11,909
Amortization of investment security premiums and accretion of discounts, net	2,745	3,140
Amortization of mortgage servicing rights	1,265	2,267
Mortgage servicing asset (recoveries) impairments		230
Deferred income taxes	(3,265)	(4,817)
Investment securities and other investment gains	(469)	(492)
Originations of loans held for sale, net of principal collected	(85,010)	(165,577)
Proceeds from the sales of loans held for sale	91,395	160,301
Net gain on sale of loans held for sale	(2,663)	(4,933)
Change in trading account securities	(31)	(13)
Change in interest receivable	(215)	(634)
Change in interest payable	(1,506)	(529)
Change in other assets	13,085	10,993
Change in other liabilities	(3,636)	404
Other	825	990
Net change in operating activities	68,653	58,636
Investing activities:
Proceeds from sales of investment securities	47,028	40,736
Proceeds from maturities of investment securities	152,706	203,436
Purchases of investment securities	(172,789)	(226,567)
Net change in other investments	200	(3,390)
Loans sold or participated to others	25,054	22,968
Net change in loans and leases	(171,771)	(206,261)
Net change in equipment owned under operating leases	(18,732)	(854)
Purchases of premises and equipment	(4,040)	(6,521)
Net change in investing activities	(142,344)	(176,453)
Financing activities:
Net change in demand deposits, NOW accounts and savings accounts	79,907	119,128
Net change in certificates of deposit	(24,838)	(70,601)
Net change in short-term borrowings	52,254	11,401
Proceeds from issuance of long-term debt	5,951	26,873
Payments on long-term debt	(20,313)	(360)
Net proceeds from issuance of treasury stock	3,650	3,743
Acquisition of treasury stock	(2,268)	(2,617)
Cash dividends paid on common stock	(12,820)	(12,263)
Net change in financing activities	81,523	75,304
Net change in cash and cash equivalents	7,832	(42,513)
Cash and cash equivalents, beginning of year	83,934	114,327
Cash and cash equivalents, end of period	91,766	71,814
Non-cash transactions:
Loans transferred to other real estate and repossessed assets	5,717	2,319
Common stock matching contribution to Employee Stock Ownership and Profit Sharing Plan	$ 2,801	$ 2,643