Acquisition - Preliminary Purchase Price Allocation (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	9 Months Ended
	Feb. 28, 2013	Sep. 30, 2013
Business Combinations [Abstract]
Purchase price	$ 46,683
Less: acquired cash	(8,856)
Purchase price, net of acquired cash	37,827	37,827
Accounts receivable	3,733
Intangible assets	13,255
Other assets	1,718
Deferred tax liability, net	(2,342)
Accounts payable, accrued expenses and deferred revenue	(4,622)
Goodwill	$ 26,085