Goodwill and Amortizable Intangible Assets - Net Consolidated Balance of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 41,579
Accumulated Amortization	(25,496)
Total amortizable intangible assets	$ 16,083	$ 19,698
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	10 years
Gross Carrying Amount	$ 25,002
Accumulated Amortization	(11,459)
Total amortizable intangible assets	13,543
Acquired Technology and Product License [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,453
Accumulated Amortization	(8,253)
Total amortizable intangible assets	$ 200
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	3 years
Gross Carrying Amount	$ 2,370
Accumulated Amortization	(2,324)
Total amortizable intangible assets	$ 46
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	3 years
Gross Carrying Amount	$ 5,754
Accumulated Amortization	(3,460)
Total amortizable intangible assets	$ 2,294
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	2 years
Minimum [Member] | Acquired Technology and Product License [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	2 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	10 years
Maximum [Member] | Acquired Technology and Product License [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	4 years