Acquired Intangible Assets (Details) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013	Jun. 30, 2014		Jun. 30, 2013	Dec. 31, 2013
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	$ 57,670,000			$ 57,670,000			$ 52,772,000
Less accumulated amortization	(21,612,000)	[1]		(21,612,000)	[1]		(19,202,000)	[1]
Net acquired intangible assets	36,058,000			36,058,000			33,570,000
Amortization of acquired intangible assets [Abstract]
Amortization expense	1,200,000		1,400,000	2,400,000		2,700,000
Estimated amortization expense, remainder of current year	2,600,000			2,600,000
Estimated amortization expense in year 2015	5,000,000			5,000,000
Estimated amortization expense in year 2016	4,900,000			4,900,000
Estimated amortization expense in year 2017	4,700,000			4,700,000
Estimated amortization expense in years 2018 through 2028	13,700,000			13,700,000
Customer Relationships [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	49,017,000			49,017,000			44,179,000
Trademarks and Trade Names [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	6,800,000			6,800,000			6,800,000
Intangible assets acquired [Abstract]
Amount of acquired indefinite-lived intangible assets	5,200,000			5,200,000
Non-compete Agreements [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	970,000			970,000			910,000
Patents and Supply Contracts [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	723,000			723,000			723,000
Leaseholds [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	160,000			160,000			160,000
Annex Manufacturing [Member] | Customer Relationships [Member]
Intangible assets acquired [Abstract]
Intangible assets acquired in business acquisition	4,700,000
Estimated useful life of intangible assets	7 years
Annex Manufacturing [Member] | Non-compete Agreements [Member]
Intangible assets acquired [Abstract]
Intangible assets acquired in business acquisition	$ 100,000
Estimated useful life of intangible assets	5 years

[1] Applies to all intangible assets, except for trademarks and trade names totaling $5.2 million, which have indefinite useful lives and, as such, are not being amortized.