Consolidated Condensed Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Assets:
Cash and due from banks	$ 117,910	$ 164,120
Money market instruments	236,016	37,185
Cash and cash equivalents	353,926	201,305
Investment securities:
Securities available-for-sale, at fair value (amortized cost of $1,067,835 and $1,099,658 at June 30, 2013 and December 31, 2012)	1,047,375	1,114,454
Securities held-to-maturity, at amortized cost (fair value of $238,519 and $410,705 at June 30, 2013 and December 31, 2012)	231,787	401,390
Other investment securities	65,907	65,907
Total investment securities	1,345,069	1,581,751
Loans	4,510,716	4,450,322
Allowance for loan losses	(55,111)	(55,537)
Net loans	4,455,605	4,394,785
Bank owned life insurance	167,740	161,069
Goodwill and other intangible assets	72,446	72,671
Bank premises and equipment, net	56,822	53,751
Other real estate owned	35,662	35,718
Accrued interest receivable	18,840	19,710
Mortgage loan servicing rights	8,260	7,763
Other	126,103	114,280
Total assets	6,640,473	6,642,803
Liabilities and Stockholders' Equity:
Noninterest bearing	1,095,454	1,137,290
Interest bearing	3,755,860	3,578,742
Total deposits	4,851,314	4,716,032
Short-term borrowings	223,489	344,168
Long-term debt	783,136	781,658
Subordinated debentures and notes	80,250	80,250
Accrued interest payable	3,232	3,459
Other	59,833	66,870
Total liabilities	6,001,254	5,992,437
COMMITMENTS AND CONTINGENCIES
Stockholders' equity:
Common stock (No par value; 20,000,000 shares authorized; 16,150,966 shares issued at June 30, 2013 and 16,150,987 shares issued at December 31, 2012)	302,653	302,654
Retained earnings	453,375	441,605
Treasury stock (738,989 shares at June 30, 2013 and at December 31, 2012)	(76,375)	(76,375)
Accumulated other comprehensive (loss), net of taxes	(40,434)	(17,518)
Total stockholders' equity	639,219	650,366
Total liabilities and stockholders' equity	$ 6,640,473	$ 6,642,803