Pension Plans (Details 2) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Components of net periodic pension cost
Interest cost	$ 213,000	$ 213,000
Expected return on plan assets	(247,000)	(227,000)
Recognized net actuarial loss	25,000	14,000
Total net periodic pension cost	(9,000)
Contributions under the defined contribution 401(k) plan	$ 223,000	$ 217,000