Pension Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Service cost - benefits earned during the period	$ 36	$ 69	$ 164	$ 204
Interest cost	393	418	1,177	1,255
Expected return on plan assets	$ (713)	$ (695)	$ (2,133)	$ (2,084)
Amortization of transition obligation
Amortization of net (gain)/loss	$ (16)	$ (56)	$ (63)	$ (166)
Amortization of prior service cost
Net periodic pension cost (income)	$ (300)	$ (264)	$ (855)	$ (791)
Pension Plan [Member]
Service cost - benefits earned during the period
Interest cost	$ 341	$ 365	$ 1,023	$ 1,096
Expected return on plan assets	$ (713)	$ (695)	$ (2,133)	$ (2,084)
Amortization of transition obligation
Amortization of net (gain)/loss
Amortization of prior service cost
Net periodic pension cost (income)	$ (372)	$ (330)	$ (1,110)	$ (988)
SERP [Member]
Service cost - benefits earned during the period	36	69	164	204
Interest cost	$ 52	$ 53	$ 154	$ 159
Expected return on plan assets
Amortization of transition obligation
Amortization of net (gain)/loss	$ (16)	$ (56)	$ (63)	$ (166)
Amortization of prior service cost
Net periodic pension cost (income)	$ 72	$ 66	$ 255	$ 197