Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	$ 112,353	$ 106,164
Accumulated Amortization	(81,850)	(82,106)
Customer Relationships
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	48,856	49,808
Accumulated Amortization	(47,785)	(48,895)
Amortization Period (Years)	2 years
Trade Names
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	7,786	10,600
Accumulated Amortization	(2,181)	(3,926)
Amortization Period (Years)	3 years
Patents
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	8,428	718
Accumulated Amortization	(584)	(52)
Amortization Period (Years)	5 years
Other
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	32,986	29,798
Accumulated Amortization	(31,300)	(29,233)
Amortization Period (Years)	2 years
Trademarks/Internet domains
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	$ 14,297	$ 15,240