Loans and Allowance for Credit Losses (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Loans and Allowance for Credit Losses (Textual) [Abstract]
Loans increased	$ 115,900,000		$ 115,900,000
Percentage of loans decreased	3.00%		3.00%
Portfolio loans	4,159,531,000	3,992,058,000	4,159,531,000	3,992,058,000	4,043,643,000
Charge-offs	3,749,000	11,194,000	8,741,000	19,802,000
Loans held for sale	0		0		13,412,000
Nonaccrual	78,692,000		78,692,000		78,476,000
Financing receivable recorded investment nonaccrual status remaining portion	20,800,000		20,800,000
Loans with modifications to rate and payment due to reamortization	18,000	15,000
Loans and Allowance for Credit Losses (Additional Textual) [Abstract]
Minimum days required for conversion of trouble debt to be in default			90 days
Criticized Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Loans increased	19,500,000		19,500,000
Percentage of loans decreased	7.00%		7.00%
Loans designated as substandard or doubtful	272,500,000		272,500,000
Percentage of loan portfolio	7.00%		7.00%
Increase in nonperforming loans			3,800
Accruing Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Loans increased	1,900,000		1,900,000
Percentage of loans decreased	5.00%		5.00%
Nonaccrual Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Loans increased	200,000		200,000
Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Increase in nonperforming loans			13,800,000
Nonperforming loans	84,900,000		84,900,000		98,800,000
Increase decrease in nonperforming loans related to payoff	11,300,000		9,100,000
Decrease in specific allowance for nonperforming loans			1,500,000
Unfunded commitments related to nonperforming loans	4,800,000		4,800,000
Loans held for sale	2,900,000		2,900,000		13,400,000
Nonaccrual	19,400,000		19,400,000
Troubled debt restructured loans decreased			14,000,000	0
Loans with modifications to rate and payment due to reamortization			100,000	300,000
Commitments related to troubled debt restructured loans increased			12,600,000
Troubled debt restructuring		200,000
Commercial, Financial, Agricultural and Other [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Portfolio loans	1,059,675,000		1,059,675,000		996,739,000
Nonaccrual	27,758,000		27,758,000		33,459,000
Real Estate Construction [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Portfolio loans	77,442,000		77,442,000		76,564,000
Nonaccrual	15,060,000		15,060,000		14,911,000
Residential Real Estate [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Portfolio loans	1,213,610,000		1,213,610,000		1,137,059,000
Nonaccrual	3,923,000		3,923,000		3,153,000
Commercial Real Estate [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Portfolio loans	1,232,270,000		1,232,270,000		1,267,432,000
Nonaccrual	31,951,000		31,951,000		26,953,000
Commercial Real Estate [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonperforming commercial real estate loans			4,900,000
Loans to Individuals [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Portfolio loans	576,534,000		576,534,000		565,849,000
Nonaccrual	0		0		0
Reserve for Off-balance Sheet Activities [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Off balance sheet reserve to nonperforming loans	39,000		39,000
Construction Loan in Florida [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Charge-offs				7,700,000
Construction Loan in Florida [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonaccrual	5,700,000		5,700,000
Financing receivable recorded investment nonaccrual status remaining portion	15,100,000		15,100,000
Commercial Loan [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Charge-offs			1,200,000	2,000,000
Commercial Loan [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Loans receivable	21,000,000		21,000,000
Eastern Pennsylvania [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonaccrual	16,300,000		16,300,000
Nonaccrual loans charge off			4,200,000
Western Pennsylvania [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Charge-offs				3,100,000
Western Pennsylvania [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Financing receivable recorded investment nonaccrual status remaining portion	44,100,000		44,100,000
Principal payment of nonaccrual loans			8,000,000
Nonaccrual loans charge off			15,400,000
Nonperforming loans paid off				2,200,000
Commercial real estate loan for retail development in Western Pennsylvania [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonaccrual	4,900,000		4,900,000
Waste Management Company in Pennsylvania [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Increase decrease in nonperforming loans related to payoff			11,300,000
Nevada Developer [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonaccrual	3,400,000		3,400,000
Commercial construction loan	8,900,000		8,900,000
Commercial construction loan charge off	5,200,000		5,200,000
Medical Equipment [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Impaired loans under nonperforming status			2,500,000
Residential Lot Development [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Impaired loans under nonperforming status			1,300,000
Water Treatment Plant [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonaccrual	2,800,000		2,800,000
Gas Well Servicing Operation [Member] | Impaired Loans [Member]
Loans and Allowance for Credit Losses (Textual) [Abstract]
Nonaccrual	$ 3,700,000		$ 3,700,000