Acquisition - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Xtrakter Limited [Member]	Feb. 28, 2013 Xtrakter Limited [Member]
Business Acquisition [Line Items]
Aggregate business acquisition purchase price	$ 37,827,000		$ 37,827,000			$ 37,800,000
Professional services					1,600,000
Revenue	65,559,000	48,825,000	121,116,000	99,560,000	7,400,000
Net income					$ 300,000