Loans (Troubled Debt Restructurings Subsequent Default) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 loan		Dec. 31, 2011 loan
Commercial Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	6		2
Commercial Construction and Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Commercial Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	8		13
Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	2		8
Homeowner Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Home Equity Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		1
Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	2		2
Class of Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	18		26
Payment Default [Member] | Commercial Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	1		2
Recorded Investment on Modifications with Subsequent Default	195	[1]	215	[1]
Payment Default [Member] | Commercial Construction and Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Recorded Investment on Modifications with Subsequent Default	0	[1]	0	[1]
Payment Default [Member] | Commercial Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	3		11
Recorded Investment on Modifications with Subsequent Default	866	[1]	937	[1]
Payment Default [Member] | Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		3
Recorded Investment on Modifications with Subsequent Default	0	[1]	913	[1]
Payment Default [Member] | Homeowner Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Recorded Investment on Modifications with Subsequent Default	0	[1]	0	[1]
Payment Default [Member] | Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Recorded Investment on Modifications with Subsequent Default	0	[1]	0	[1]
Payment Default [Member] | Home Equity Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Recorded Investment on Modifications with Subsequent Default	0	[1]	0	[1]
Payment Default [Member] | Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	0		0
Recorded Investment on Modifications with Subsequent Default	0	[1]	0	[1]
Payment Default [Member] | Class of Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	4		16
Recorded Investment on Modifications with Subsequent Default	1,061	[1]	2,065	[1]

[1] The recorded investment in troubled debt restructurings consists of unpaid principal balance, net of charge-offs and unamortized deferred loan origination fees and costs. For accruing troubled debt restructurings the recorded investment also includes accrued interest.