Premises and Equipment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of premises and equipment consisted [Abstract]
Premises and equipment, gross	$ 57,219	$ 55,880
Less: accumulated depreciation	(20,468)	(18,388)
Premises and equipment, net	36,751	37,492
Depreciation expense	2,419	2,101	1,689
Land and buildings [Member]
Summary of premises and equipment consisted [Abstract]
Premises and equipment, gross	35,892	35,892
Furniture and equipment [Member]
Summary of premises and equipment consisted [Abstract]
Premises and equipment, gross	13,477	12,879
Land improvements [Member]
Summary of premises and equipment consisted [Abstract]
Premises and equipment, gross	3,561	3,536
Computer software [Member]
Summary of premises and equipment consisted [Abstract]
Premises and equipment, gross	3,689	3,364
Construction in progress [Member]
Summary of premises and equipment consisted [Abstract]
Premises and equipment, gross	$ 600	$ 209