Business Combinations (Details Textual) (USD $)	3 Months Ended							6 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2012	Jun. 30, 2011	Sep. 23, 2011
Business Combinations (Textual) [Abstract]
Net assets transferred to Bank										$ 270,304,000
Interest expense	2,010,000	2,128,000	2,329,000		2,465,000	2,714,000	2,730,000	4,138,000	5,444,000
Noninterest income	10,577,000	8,265,000	10,489,000	8,029,000	14,723,000	8,251,000	9,350,000	18,842,000	17,601,000
Amount of fair value discount accretion included in interest income				3,146,000
Loss on disposal of fixed assets related to system conversion	(153,000)					(6,000)		(388,000)	(15,000)
Data processing and software	1,143,000					956,000		2,572,000	1,808,000
Citizens acquisition [Member]
Business Combinations (Textual) [Abstract]
Bargain purchase gain on acquisition	1,534,000	2,354,000
Net assets transferred to Bank										26,682,000
Term of Lease Expiration				90 days
Interest income	5,032,000	4,584,000		6,171,000
Interest expense	5,000	8,000		54,000
Provision for loan losses	281,000	1,467,000		1,462,000
Noninterest income	643,000	145,000
Noninterest expense	1,534,000	2,354,000
Amount of fair value discount accretion included in interest income	2,278,000	1,972,000
Loss on disposal of fixed assets related to system conversion		230,000
Data processing and software		415,000
Acquisition method of accounting [Member] | Citizens acquisition [Member]
Business Combinations (Textual) [Abstract]
Bargain purchase gain on acquisition				7,575,000
Noninterest expense				7,575,000
Noninterest expense [Member]
Business Combinations (Textual) [Abstract]
Bargain purchase gain on acquisition				1,865,000
Noninterest expense				$ 1,865,000