Acquisitions and Divestitures Acquisitions and Divestitures (Summary of Fair Value of Assets Acquired and Liabilities Assumed) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Current Assets	$ 14,552
Business Acquisition, Purchase Price Allocation, Plant and Equipment	25,453
Business Acquisition, Purchase Price Allocation, Goodwill Amount	36,814
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	37,188
Business Acquisition, Purchase Price Allocation, Current Liabilities	(14,716)
Business Acquisition, Purchase Price Allocation, Non-current Liabilities	(4,661)
Business Acquisition, Cost of Acquired Entity, Cash Paid	94,630
All Other Operations Business Segment [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Current Assets	534
Business Acquisition, Purchase Price Allocation, Plant and Equipment	1,169
Business Acquisition, Purchase Price Allocation, Goodwill Amount	2,509
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	2,000
Business Acquisition, Purchase Price Allocation, Current Liabilities	(2,551)
Business Acquisition, Purchase Price Allocation, Non-current Liabilities	(722)
Business Acquisition, Cost of Acquired Entity, Cash Paid	2,939
Distribution Business Segment [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Current Assets	14,018
Business Acquisition, Purchase Price Allocation, Plant and Equipment	24,284
Business Acquisition, Purchase Price Allocation, Goodwill Amount	34,305
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	35,188
Business Acquisition, Purchase Price Allocation, Current Liabilities	(12,165)
Business Acquisition, Purchase Price Allocation, Non-current Liabilities	(3,939)
Business Acquisition, Cost of Acquired Entity, Cash Paid	$ 91,691