Acquired Intangible Assets (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets		$ 57,349		$ 57,349		$ 57,299
Less accumulated amortization	[1]	(26,661)		(26,661)		(24,120)
Net acquired intangible assets		30,688		30,688		33,179
Amortization of acquired intangible assets [Abstract]
Amortization expense		1,200	$ 1,200	2,500	$ 2,400
Estimated amortization expense, remainder of current year		2,500		2,500
Estimated amortization expense in year 2016		4,900		4,900
Estimated amortization expense in year 2017		4,700		4,700
Estimated amortization expense in year 2018		4,500		4,500
Estimated amortization expense in years 2019 through 2028		8,900		8,900
Customer Relationships [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets		48,696		48,696		48,646
Trademarks and Trade Names [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets		6,800		6,800		6,800
Intangible assets acquired [Abstract]
Amount of acquired indefinite-lived intangible assets		5,200		5,200
Non-compete Agreements [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets		970		970		970
Patents and Supply Contracts [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets		723		723		723
Leaseholds [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets		$ 160		$ 160		$ 160

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