Acquisitions and Exit of Joint Venture (Exit of Joint Venture) (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 28, 2013 Audco [Member]
Schedule of Equity Method Investments [Line Items]
Proceeds from Sale of Equity Method Investments				$ 46,200,000
Percent of business acquired				100.00%
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain	15,315,000	0	0	15,300,000
Equity Method Investment, Summarized Financial Information, Assets				25,000,000
Equity Method Investment, Realized Gain (Loss) on Disposal				13,000,000
Ownership percentage				50.00%
Payments for acquisitions, net of cash acquired	$ 76,801,000	$ 3,996,000	$ 90,505,000	$ 10,100,000
Ownership percentage				50.00%