Pension Plans (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
Pension Plan
Service cost - benefits earned during the period	$ 386	$ 478	$ 1,449	$ 1,434
Interest cost	326	432	1,125	1,296
Expected return on plan assets	(492)	(444)	(1,477)	(1,332)
Amortization of transition obligation		1	2	3
Amortization of net (gain)/loss	71	114	474	342
Amortization of prior service cost	3	3	9	9
Net periodic pension cost	294	584	1,582	1,752
SERP
Service cost - benefits earned during the period	67	99	236	345
Interest cost	61	102	219	306
Expected return on plan assets
Amortization of transition obligation
Amortization of net (gain)/loss	(17)	26	17	78
Amortization of prior service cost	5	5	14	15
Net periodic pension cost	116	232	486	744
2012 Total Both Plans
Service cost - benefits earned during the period	453		1,685
Interest cost	387		1,344
Expected return on plan assets	(492)		(1,477)
Amortization of transition obligation			2
Amortization of net (gain)/loss	54		491
Amortization of prior service cost	8		23
Net periodic pension cost	410		2,068
2011 Total Both Plans
Service cost - benefits earned during the period		577		1,779
Interest cost		534		1,602
Expected return on plan assets		(444)		(1,332)
Amortization of transition obligation		1		3
Amortization of net (gain)/loss		140		420
Amortization of prior service cost		8		24
Net periodic pension cost		$ 816		$ 2,496