Intangible Assets - Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	2 years 8 months 12 days
Gross Carrying Amount	$ 17,900	$ 17,701
Accumulated Amortization	(12,942)	(10,658)
Total intangible assets	4,958	7,043
Customer, Affiliate and Advertiser Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,146	7,067
Accumulated Amortization	(4,563)	(3,586)
Total intangible assets	2,583	3,481
Developed Websites, Technology and Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,942	6,874
Accumulated Amortization	(5,721)	(5,100)
Total intangible assets	1,221	1,774
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,044	2,026
Accumulated Amortization	(1,482)	(1,152)
Total intangible assets	562	874
Proprietary User Information Database and Internet Traffic [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,318	1,295
Accumulated Amortization	(789)	(519)
Total intangible assets	529	776
Non-compete Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	450	439
Accumulated Amortization	(387)	(301)
Total intangible assets	$ 63	$ 138
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	2 years
Minimum [Member] | Customer, Affiliate and Advertiser Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	5 years	4 years
Minimum [Member] | Developed Websites, Technology and Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	6 years	3 years
Minimum [Member] | Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	5 years	1 year
Minimum [Member] | Proprietary User Information Database and Internet Traffic [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	3 years
Minimum [Member] | Non-compete Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	2 years	2 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	10 years
Maximum [Member] | Customer, Affiliate and Advertiser Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	9 years	9 years
Maximum [Member] | Developed Websites, Technology and Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	10 years	10 years
Maximum [Member] | Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	8 years	8 years
Maximum [Member] | Proprietary User Information Database and Internet Traffic [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	5 years	5 years
Maximum [Member] | Non-compete Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	3 years	3 years