Employee Benefits Plans (Details 13) (Other Postretirement Benefits [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Other Postretirement Benefits [Member]
Amounts recognized in the Consolidated Balance Sheets
Current liability	$ 2,414	$ 2,683
Noncurrent liability	28,374	37,916
Net amount recognized	30,788	40,599
Amounts recognized in accumulated other comprehensive loss (pre-tax)
Prior service credit	(4,986)	(1,307)
Net actuarial loss	(6,239)	(859)
Net amount recognized	$ (11,225)	$ (2,166)