Acquisitions (Summary Of Fair Values Of The Assets Acquired And Liabilities Assumed) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Business Acquisition [Line Items]
Current assets, net	$ 15,135
Plant and equipment	47,122
Goodwill	27,826
Other intangible assets	21,066
Current liabilities	(9,709)
Non-current liabilities	(4,470)
Total cash consideration	96,970
Distribution Business Segment [Member]
Business Acquisition [Line Items]
Current assets, net	10,193
Plant and equipment	29,139
Goodwill	17,734	[1]
Other intangible assets	15,936
Current liabilities	(8,683)
Non-current liabilities	(1,183)
Total cash consideration	63,136
All Other Operations Business Segment [Member]
Business Acquisition [Line Items]
Current assets, net	4,942
Plant and equipment	17,983
Goodwill	10,092	[1]
Other intangible assets	5,130
Current liabilities	(1,026)
Non-current liabilities	(3,287)
Total cash consideration	$ 33,834

[1] Includes current acquisitions and adjustments made to prior year acquisitions.