Business Combinations - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands			9 Months Ended
	Feb. 12, 2015	Jun. 02, 2014	Sep. 30, 2015
Business Acquisition [Line Items]
Number of RSUs, granted			1,137
SocialMoov [Member]
Business Acquisition [Line Items]
Acquisition date			Feb. 12, 2015
Business acquisition, purchase price	$ 13,195
Number of common stock, shares at the date of acquisition	636
Consideration in common stock	$ 4,337
Common stock value at the date of acquisition	8,858
Held in escrow to secure indemnification obligations	$ 1,894
Additional shares of common stock issued in connection with acquisition	927
Common stock issued in connection with acquisition closing date fair value	$ 6,487
SocialMoov [Member] | RSUs [Member]
Business Acquisition [Line Items]
Number of RSUs, granted	219
Value of RSUs, granted	$ 959
NowSpots, Inc. [Member]
Business Acquisition [Line Items]
Acquisition date			Jun. 02, 2014
Business acquisition, purchase price		$ 16,470
Number of common stock, shares at the date of acquisition		1,119
Consideration in common stock		$ 6,301
Common stock value at the date of acquisition		$ 5,275
Additional shares of common stock issued in connection with acquisition		630