Business and Basis of Presentation (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
	Mar. 07, 2014 employee	Mar. 31, 2014
Business Acquisition [Line Items]
Number of reportable segments		3
Software Advice, Inc.
Business Acquisition [Line Items]
Number of employees	120
Cash payment to acquire business	$ 103.2
Percentage of voting interests acquired	100.00%
Contingent consideration amount, maximum	31.9
Acquisition and integration charges		3.4
Goodwill deductible period	15 years
Contingent Escrow Deposit | Software Advice, Inc.
Business Acquisition [Line Items]
Contingent consideration amount, maximum	13.5
Contingent Payable | Software Advice, Inc.
Business Acquisition [Line Items]
Contingent consideration amount, maximum	$ 18.4