Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Interest Income
Interest and fees on loans	$ 197,897	$ 192,247	$ 172,388
Interest on investment securities:
Taxable	9,423	11,363	15,385
Tax-exempt	5,860	4,999	3,596
Dividends on nonmarketable equity securities	965	766	821
Interest on deposits with unaffiliated banks and others	1,097	1,055	541
Total Interest Income	215,242	210,430	192,731
Interest Expense
Interest on deposits	29,293	35,895	39,500
Interest on short-term borrowings	524	650	906
Interest on FHLB advances	1,572	2,765	4,881
Total Interest Expense	31,389	39,310	45,287
Net Interest Income	183,853	171,120	147,444
Provision for loan losses	26,000	45,600	59,000
Net Interest Income after Provision for Loan Losses	157,853	125,520	88,444
Noninterest Income
Service charges on deposit accounts	18,452	18,562	19,116
Wealth management revenue	11,104	10,106	9,273
Other charges and fees for customer services	10,501	9,599	7,736
Mortgage banking revenue	3,881	3,925	4,412
Investment securities gains			95
Other	462	280	487
Total Noninterest Income	44,400	42,472	41,119
Operating Expenses
Salaries, wages and employee benefits	74,493	68,416	60,218
Occupancy	12,974	11,491	10,359
Equipment and software	11,935	13,446	9,723
Other	42,601	43,449	37,310
Total Operating Expenses	142,003	136,802	117,610
Income Before Income Taxes	60,250	31,190	11,953
Federal income tax expense	17,200	8,100	1,950
Net Income	$ 43,050	$ 23,090	$ 10,003
Net Income Per Common Share
Basic	$ 1.57	$ 0.88	$ 0.42
Diluted	$ 1.57	$ 0.88	$ 0.42
Cash Dividends Declared Per Common Share	$ 0.80	$ 0.80	$ 1.18