Employee Benefits (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Benefits (Textual) [Abstract]
Expected to contribute Pension Plan	$ 1,000,000
Benefit expected to be paid in 2013	987,000
Benefit expected to be paid in 2014	1,032,000
Benefit expected to be paid in 2015	1,105,000
Benefit expected to be paid in 2016	1,167,000
Benefit expected to be paid in 2017	1,237,000
Aggregate benefits expected to paid	7,158,000
Employee Benefits (Additional Textual) [Abstract]
Contributions matched by compensation contribution	6.00%
Voluntary contribution of employees	33.30%
Voluntary contribution of employees, Amount	308,000	266,000	244,000
Discretionary bonus expense	1,289,000	1,100,000	600,000
Supplemental Insurance/ Retirement Plan [Member]
Employee Benefits (Textual) [Abstract]
Benefit expected to be paid in 2013	1,102,000
Benefit expected to be paid in 2014	1,098,000
Benefit expected to be paid in 2015	1,080,000
Benefit expected to be paid in 2016	1,494,000
Benefit expected to be paid in 2017	1,938,000
Aggregate benefits expected to paid	$ 9,840,000
Equity Securities [Member]
Employee Benefits (Textual) [Abstract]
Allocation mix for the common and collective trust portfolio, Minimum	40.00%
Allocation mix for the common and collective trust portfolio, Maximum	64.00%
Short-term investments [Member]
Employee Benefits (Textual) [Abstract]
Allocation mix for the common and collective trust portfolio, Minimum	15.00%
Allocation mix for the common and collective trust portfolio, Maximum	25.00%
Hedge funds [Member]
Employee Benefits (Textual) [Abstract]
Allocation mix for the common and collective trust portfolio, Minimum	20.00%
Allocation mix for the common and collective trust portfolio, Maximum	36.00%