Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Pension Benefit Plan [Member]
Periodic costs for employee retirement benefit plans
Service Cost	$ 474	$ 575	$ 947	$ 1,150
Interest Cost	671	617	1,341	1,234
Expected Return on Assets	(884)	(723)	(1,767)	(1,447)
Amortization of Unrecognized Losses	104	408	208	816
Amortization of Unrecognized Prior Service Cost (Credit)		3	1	5
Net Periodic Benefit Cost	365	880	730	1,758
Other Benefits Plan [Member]
Periodic costs for employee retirement benefit plans
Service Cost	258	335	516	669
Interest Cost	448	398	896	797
Expected Return on Assets	(484)	(405)	(969)	(811)
Amortization of Unrecognized Losses	353	517	707	1,033
Amortization of Unrecognized Prior Service Cost (Credit)	(432)	(432)	(864)	(864)
Net Periodic Benefit Cost	$ 143	$ 413	$ 286	$ 824