Loans (Loans Sold) (Details) (USD $)	3 Months Ended
	Mar. 31, 2013 loans	Mar. 31, 2012 loans	Dec. 31, 2012
Financing Receivable [Line Items]
Net deferred loan premiums (discounts)	$ (2,600,000)		$ 3,600,000
Unpaid principal balance for loans serviced for others	109,700,000		65,100,000
Number of loans sold	0	2
Recorded investment of loans sold	0	3,950,000
Contract pricing of loans sold	0	4,200,000
Commercial and agricultural [Member]
Financing Receivable [Line Items]
Number of loans sold	0	0
Recorded investment of loans sold	0	0
Contract pricing of loans sold	0	0
Real estate - construction [Member]
Financing Receivable [Line Items]
Number of loans sold	0	1
Recorded investment of loans sold	0	3,800,000
Contract pricing of loans sold	0	4,050,000
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable [Line Items]
Number of loans sold		1
Recorded investment of loans sold		150,000
Contract pricing of loans sold		150,000
Real estate - mortgage, commercial [Member]
Financing Receivable [Line Items]
Number of loans sold	0	0
Recorded investment of loans sold	0	0
Contract pricing of loans sold	0	0
Consumer [Member]
Financing Receivable [Line Items]
Number of loans sold	0	0
Recorded investment of loans sold	0	0
Contract pricing of loans sold	$ 0	$ 0