Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
ASSETS
Cash and due from banks	$ 139,004	$ 163,698	$ 146,904
Interest-bearing deposits with banks	1,773,610	1,544,035	1,463,388
Federal funds sold		400
Securities (market value: $540,786, $615,458, and $607,626, respectively)	540,475	614,977	607,046
Loans:
Total loans (net of unearned interest)	3,116,096	3,013,498	2,984,114
Allowance for loan losses	(37,258)	(37,656)	(37,456)
Loans, net	3,078,838	2,975,842	2,946,658
Premises and equipment, net	113,812	111,355	110,001
Other real estate owned	9,559	16,109	16,222
Intangible assets, net	12,630	14,219	14,883
Goodwill	44,545	44,545	44,593
Accrued interest receivable	16,666	18,662	17,657
Other assets	107,612	104,983	104,954
Total assets	5,836,751	5,608,825	5,472,306
LIABILITIES AND STOCKHOLDERS' EQUITY
Noninterest-bearing	1,927,387	1,704,996	1,624,314
Interest-bearing	3,326,118	3,332,739	3,263,018
Total deposits	5,253,505	5,037,735	4,887,332
Short-term borrowings	5,665	8,274	12,279
Accrued interest payable	2,151	2,710	2,874
Long-term borrowings	11,255	18,476	28,049
Other liabilities	26,984	22,506	31,293
Junior subordinated debentures	26,804	36,083	36,083
Total liabilities	5,326,364	5,125,784	4,997,910
Commitments and contingent liabilities
Stockholders' equity:
Common stock, $1.00 par, 20,000,000 shares authorized; shares issued and outstanding: 15,200,468, 15,117,430 and 15,125,541, respectively	15,200	15,118	15,126
Capital surplus	80,750	77,462	74,966
Retained earnings	407,732	381,017	374,140
Accumulated other comprehensive income, net of income tax of $3,609, $5,084 and 5,484, respectively	6,705	9,444	10,164
Total stockholders' equity	510,387	483,041	474,396
Total liabilities and stockholders' equity	5,836,751	5,608,825	5,472,306
Senior preferred stock
Stockholders' equity:
Preferred stock, value
Cumulative preferred stock
Stockholders' equity:
Preferred stock, value