Acquisitions (Effect of the acquisition on Consolidated Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Acquisitions In 2012
Effect of acquisition on current assets [Abstract]
Current assets				$ 30
Property, plant & equipment				5,964
Goodwill	221,087	218,442	193,962	3,843
Deferred charges and other non-current assets	(5,430)	(1,605)		3,825
Accrued liabilities				(12)
Cash paid	$ 13,700	$ 42,700		$ 13,650