Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue:
Consumer revenue	$ 559,467	$ 449,193	$ 340,121
Enterprise revenue	28,002	26,823	29,537
Total revenue	587,469	476,016	369,658
Cost of services	137,356	120,422	100,065
Gross profit	450,113	355,594	269,593
Costs and expenses:
Sales and marketing	273,389	213,984	162,363
Technology and development	69,115	50,973	40,015
General and administrative	183,259	75,673	42,125
Amortization of acquired intangible assets	9,103	8,898	7,909
Total costs and expenses	534,866	349,528	252,412
Income (loss) from operations	(84,753)	6,066	17,181
Other income (expense):
Interest expense	(371)	(353)	(353)
Interest income	770	281	124
Other, net	(189)	(137)	(21)
Total other income (expense)	210	(209)	(250)
Income (loss) before provision for income taxes	(84,543)	5,857	16,931
Income tax (benefit) expense	(33,540)	3,362	(37,524)
Net income (loss)	$ (51,003)	$ 2,495	$ 54,455
Net income (loss) per share
Basic (USD per share)	$ (0.54)	$ 0.03	$ 0.61
Diluted (USD per share)	$ (0.54)	$ 0.03	$ 0.57
Weighted-average common shares outstanding used in computing net income (loss) per share:
Basic (shares)	94,897,450	92,733,496	88,635,832
Diluted (shares)	94,897,450	99,101,932	96,046,744