Loans (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Information relating to loans
NET LOAN BALANCES (1)	$ 1,265,893	$ 1,226,081
Construction and land development [Member]
Information relating to loans
NET LOAN BALANCES (1)	61,116	60,736
Commercial real estate [Member]
Information relating to loans
NET LOAN BALANCES (1)	513,598	486,828
Residential real estate [Member]
Information relating to loans
NET LOAN BALANCES (1)	581,378	569,331
Commercial and financial [Member]
Information relating to loans
NET LOAN BALANCES (1)	65,224	61,903
Consumer [Member]
Information relating to loans
NET LOAN BALANCES (1)	44,296	46,930
Other loans [Member]
Information relating to loans
NET LOAN BALANCES (1)	$ 281	$ 353