Acquisitions and Investments (Narrative) (Details) (USD $)	6 Months Ended					0 Months Ended	2 Months Ended					3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Industrial	Jun. 30, 2013 Industrial	May 13, 2014 Specialized Industries LP	Jun. 30, 2014 Specialized Industries LP	May 13, 2014 Specialized Industries LP	May 13, 2014 Specialized Industries LP Industrial	May 13, 2014 Specialized Industries LP Amended and Restated Revolving Credit Agreement Revolving Credit Facility	May 12, 2014 Specialized Industries LP Amended and Restated Revolving Credit Agreement Revolving Credit Facility	Jun. 30, 2014 Smaller immaterial acquisitions Aquisition
Business Acquisition [Line Items]
Total consideration for the purchase						$ 193,000,000						$ 6,204,000
Amount of line of credit										250,000,000	100,000,000
Borrowings on bank revolving credit facility	200,000,000	0				190,000,000
Acquisition related costs incurred							1,700,000
Goodwill	73,594,000	30,923,000	32,073,000	52,543,000	13,210,000			39,383,000	39,400,000
Net revenue generated since closing date							19,000,000
Net income generated since closing date							$ 1,500,000
Number of businesses acquired												2