Summary of Significant Accounting Policies (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012 Contract	Jun. 30, 2011	Jun. 30, 2012 Contract Branches Offices	Jun. 30, 2011
Summary of Significant Accounting Policies (Additional Textual) [Abstract]
Number of full service banking branches			25
Number of loan production offices			1
Stock-based compensation expense	$ 103,000	$ 96,000	$ 211,000	$ 196,000
Tax benefit from compensation expense	8,000	6,500	17,000	13,100
Unrecognized compensation cost	710,000		710,000
Share-based compensation expense recognized, years			4 years
Interest rate cap contracts outstanding	16		16
Number of interest rate swap contracts			2
Interest payment in junior subordinated notes	35,000,000		35,000,000
Minimum cumulative percentage change in anticipated cash flows			80.00%
Maximum cumulative percentage change in anticipated cash flows			125.00%
Maximum probability of threshold percentage			50.00%
Deemed effective interest rate swaps			0
Gain (loss) to be reclassified during next 12 months	0		0
AMSCO [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Ownership percentage			51.00%
Interest rate caps [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Notional amounts of interest rate cap contracts	$ 170,000,000		$ 170,000,000