Consolidated Statements of Financial Position (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Cash and cash equivalents:
Cash and cash due from banks	$ 142,467	$ 121,294
Interest-bearing deposits with the Federal Reserve Bank	513,668	260,646
Total cash and cash equivalents	656,135	381,940
Investment securities:
Available-for-sale, at fair value	586,809	667,276
Held-to-maturity, at amortized cost (fair value - $229,922 at December 31, 2012 and $183,769 at December 31, 2011)	229,977	183,339
Total investment securities	816,786	850,615
Loans held-for-sale	17,665	18,818
Loans	4,167,735	3,831,285
Allowance for loan losses	(84,491)	(88,333)
Net loans	4,083,244	3,742,952
Premises and equipment	75,458	65,997
Goodwill	120,164	113,414
Other intangible assets	15,388	11,472
Interest receivable and other assets	132,412	154,245
Total Assets	5,917,252	5,339,453
Deposits:
Noninterest-bearing	1,085,857	875,791
Interest-bearing	3,835,586	3,491,066
Total deposits	4,921,443	4,366,857
Interest payable and other liabilities	54,716	54,024
Short-term Borrowings	310,463	303,786
Federal Home Loan Bank (FHLB) advances	34,289	43,057
Total liabilities	5,320,911	4,767,724
Shareholders' equity:
Preferred stock, no par value: Authorized - 200,000 shares, none issued	0	0
Common stock, $1 par value per share: Authorized - 45,000,000 shares; issued and outstanding - 27,498,868 shares at December 31, 2012 and 27,456,907 shares at December 31, 2011	27,499	27,457
Additional paid-in capital	433,195	431,277
Retained earnings	166,766	138,324
Accumulated other comprehensive loss	(31,119)	(25,329)
Total shareholders' equity	596,341	571,729
Total Liabilities and Shareholders' Equity	$ 5,917,252	$ 5,339,453