Goodwill and Amortizable Intangible Assets - Net Consolidated Balance of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 41,580
Accumulated Amortization	(27,727)
Total amortizable intangible assets	$ 13,853	$ 14,964
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	10 years
Gross Carrying Amount	$ 25,002
Accumulated Amortization	(12,710)
Total amortizable intangible assets	12,292
Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,454
Accumulated Amortization	(8,425)
Total amortizable intangible assets	29
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,370
Accumulated Amortization	(2,370)
Total amortizable intangible assets	$ 0
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	6 years
Gross Carrying Amount	$ 5,754
Accumulated Amortization	(4,222)
Total amortizable intangible assets	$ 1,532
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	2 years
Minimum [Member] | Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	2 years
Minimum [Member] | Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	3 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	10 years
Maximum [Member] | Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	4 years
Maximum [Member] | Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	5 years