Employee Benefits (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Benefits [Abstract]
Retirement Plan, contributions made by the employer	$ 331,000	$ 313,000	$ 321,000
Employee Stock Ownership Plan, contributions made by the employer	100,000	69,000
Employee Stock Ownership Plan, shares of common stock owned by the plan	304,781	304,281
Supplemental Executive Retirement Plan, liabilities accrued	2,950,000	3,060,000
Supplemental Executive Retirement Plan, cash surrender value of insurance contracts	$ 29,200,000	$ 29,000,000
Granting of stock options to key officers	350,000
Term of the stock option, years	10 years