Short-Term Borrowings and Long-Term Debt (Retail Repurchase Agreements and Federal Funds Purchased) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Short-term Debt [Line Items]
Short-term borrowings	$ 8,675,000	$ 8,838,000
Retail customer repurchase agreements	8,675,000	8,838,000	9,628,000
Federal funds purchased			0
Federal Reserve Bank Lines of Credit [Member]
Short-term Debt [Line Items]
Short-term borrowings	0
Retail repurchase agreements [Member]
Short-term Debt [Line Items]
Average balance during the year	9,861,000	8,973,000	13,355,000
Maximum month end balance	12,720,000	10,917,000	16,424,000
Weighted average interest rate at December 31	0.19%	0.42%	0.78%
Weighted average interest rate during the year	0.29%	0.58%	0.73%
Federal funds purchased [Member]
Short-term Debt [Line Items]
Average balance during the year			1,537,000
Maximum month end balance			$ 15,000,000
Weighted average interest rate at December 31			0.00%
Weighted average interest rate during the year			0.26%