Defined Benefit Plan (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Schedule of components of net periodic pension income
Service cost	$ 204	$ 168	$ 411	$ 339
Interest cost	124	163	249	329
Expected return on plan assets	(379)	(351)	(762)	(709)
Prior service cost amortization	11	11	22	22
Deferred loss amortization	44	54	89	110
Net periodic pension income	$ 4	$ 45	$ 9	$ 91