Pension - Periodic Benefit Cost (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
Components of net periodic benefit cost:
Interest cost	$ 17	$ 17	$ 43	$ 43
Service cost	12	12	17	18
Expected return on plan assets	(28)	(28)	(54)	(75)
Amortization of prior service costs	2	2	5	5
Amortization of actuarial loss	39	39	77	95
Net periodic benefit cost	$ 43	$ 43	$ 87	$ 85