Pension and Postretirement Benefits (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Defined Benefit Plan Disclosure [Line Items]
Contribution to defined benefit pension plan			$ 2,600	$ 0
Pension Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	82	166	246
Interest cost	93	103	305	310
Expected return on plan assets	(205)	(156)	(604)	(468)
Amortization of net losses	74	62	307	185
Net periodic plan cost	(38)	91	174	273
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	4	5	13	15
Expected return on plan assets	0	0	0	0
Amortization of net losses	4	5	11	14
Net periodic plan cost	$ 8	$ 10	$ 24	$ 29