Segment Information - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Segment	Jun. 30, 2012
Revenues From External Customers And Long Lived Assets [Line Items]
Number of reporting segments			2
Revenue	$ 48,662	$ 42,822	$ 95,001	$ 77,520
Europe
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	$ 4,800	$ 3,500	$ 9,400	$ 5,900
GoIndustry
Revenues From External Customers And Long Lived Assets [Line Items]
Segments disposal date			Jul. 05, 2012
Investorforce
Revenues From External Customers And Long Lived Assets [Line Items]
Segments disposal date			Jan. 29, 2013
Channel Intelligence
Revenues From External Customers And Long Lived Assets [Line Items]
Segments disposal date			Feb. 20, 2013