CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Interest and fees on loans
Taxable	$ 102,749	$ 104,936	$ 104,205
Tax exempt	441	471	86
Interest and dividends on securities
Taxable	8,311	13,575	16,406
Tax exempt	2,800	2,756	2,708
Interest on short-term investments	68	154	120
Total interest income	114,369	121,892	123,525
Interest on deposits	24,667	27,735	28,007
Interest on borrowings
Short-term	441	612	727
Long-term	1,590	1,465	2,138
Total interest expense	26,698	29,812	30,872
NET INTEREST INCOME	87,671	92,080	92,653
Provision for loan losses	2,549	13,800	23,947
NET INTEREST INCOME AFTER PROVISION FOR LOAN LOSSES	85,122	78,280	68,706
NONINTEREST INCOME
Wealth advisory fees	3,823	3,462	3,247
Investment brokerage fees	3,061	2,560	2,266
Service charges on deposit accounts	8,015	7,950	8,436
Loan, insurance and service fees	5,822	4,849	4,300
Merchant card fee income	1,184	1,020	1,081
Other income	2,147	1,817	2,175
Mortgage banking income	2,546	1,000	1,587
Net securities gains (losses)	(376)	(167)	4
Other-than-temporary impairment loss on available for sale securities:
Total impairment losses recognized on securities	(1,026)	(286)	(1,716)
Loss recognized in other comprehensive income	0	0	129
Net impairment loss recognized in earnings	(1,026)	(286)	(1,587)
Total noninterest income	25,196	22,205	21,509
NONINTEREST EXPENSE
Salaries and employee benefits	34,539	32,807	30,375
Net occupancy expense	3,296	3,106	2,899
Equipment costs	2,572	2,204	2,090
Data processing fees and supplies	4,378	3,655	3,931
Credit card interchange	0	2	158
Other expense	12,957	13,331	13,982
Total noninterest expense	57,742	55,105	53,435
INCOME BEFORE INCOME TAX EXPENSE	52,576	45,380	36,780
Income tax expense	17,182	14,718	12,237
NET INCOME	35,394	30,662	24,543
Dividends and accretion of discount on preferred stock	0	0	3,187
NET INCOME AVAILABLE TO COMMON SHAREHOLDERS	$ 35,394	$ 30,662	$ 21,356
BASIC WEIGHTED AVERAGE COMMON SHARES	16,323,870	16,204,952	16,120,606
BASIC EARNINGS PER COMMON SHARE	$ 2.17	$ 1.89	$ 1.32
DILUTED WEIGHTED AVERAGE COMMON SHARES	16,482,937	16,324,644	16,213,747
DILUTED EARNINGS PER COMMON SHARE	$ 2.15	$ 1.88	$ 1.32