Interim Consolidated Financial Statements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended	12 Months Ended	3 Months Ended				12 Months Ended		3 Months Ended				6 Months Ended	12 Months Ended		3 Months Ended
	Jun. 30, 2013 Research Service Revenue [Member]	Sep. 30, 2012 Research Service Revenue [Member]	Mar. 31, 2012 Research Service Revenue [Member]	Jun. 30, 2013 Research Service Revenue [Member]	Dec. 31, 2011 Research Service Revenue [Member]	Jun. 30, 2013 Technology Related Investment Funds [Member]	Mar. 31, 2013 Technology Related Investment Funds [Member]	Dec. 31, 2012 Technology Related Investment Funds [Member]	Sep. 30, 2012 Technology Related Investment Funds [Member]	Dec. 31, 2012 Technology Related Investment Funds [Member]	Dec. 31, 2011 Technology Related Investment Funds [Member]	Mar. 31, 2013 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Dec. 31, 2012 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Sep. 30, 2012 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Jun. 30, 2012 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Jun. 30, 2013 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Dec. 31, 2012 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Dec. 31, 2011 Adjustments Related to Insignificant Variances in Deferred Revenue [Member]	Dec. 31, 2012 Adjustments Related to Improper Capitalization of Software Development Costs [Member]	Sep. 30, 2012 Adjustments Related to Improper Capitalization of Software Development Costs [Member]	Jun. 30, 2012 Adjustments Related to Improper Capitalization of Software Development Costs [Member]
Adjustments related to prior period errors	$ 0.8	$ 0.1	$ (0.1)	$ 0.8	$ 0.1	$ 0.1	$ (0.1)	$ (0.1)	$ 0.6	$ 0.5	$ (1.4)	$ (0.1)	$ 0.1	$ 0.2	$ (0.2)	$ (0.1)	$ 0.1	$ (0.4)	$ (0.5)	$ 0.3	$ 0.2