Premises and Equipment (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Apr. 30, 2012 Subsidiary
Premises and Equipment, Net (Textual) [Abstract]
Related party rent expense	$ 410,000	$ 937,000	$ 902,000
Total rent expense	2,868,000	3,239,000	3,566,000
Depreciation expense	10,615,000	10,443,000	10,808,000
Interest expense capitalized for various construction projects	$ 11,000	$ 35,000	$ 65,000
Number of Bank Subsidiaries Prior to Charter Consolidation				11