UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Revenue	$ 16,105	$ 16,876	$ 36,160	$ 29,945
Costs and operating expenses:
Cost of revenue, excluding depreciation and amortization	11,883	12,644	26,328	20,690
Product development	2,394	3,625	5,385	6,177
Sales and marketing	1,453	3,095	3,375	6,032
General and administrative	7,519	8,367	14,567	16,299
Acquisition costs	0	124	0	3,432
Depreciation and amortization	2,753	3,064	5,398	5,743
Total cost and operating expenses	26,002	30,919	55,053	58,373
Operating loss	(9,897)	(14,043)	(18,893)	(28,428)
Nonoperating expenses, net	3,951	944	4,476	2,560
Loss before income taxes	(13,848)	(14,987)	(23,369)	(30,988)
Income tax expense (benefit)	15	(197)	(82)	(364)
Net loss	$ (13,863)	$ (14,790)	$ (23,287)	$ (30,624)
Net loss per share - basic and diluted (in dollars per share)	$ (0.10)	$ (0.13)	$ (0.17)	$ (0.29)
Weighted-average shares outstanding during the period - basic and diluted (in shares)	138,806,212	111,074,977	138,531,827	107,341,105
Other comprehensive income (loss):
Foreign currency translation gain (loss)	$ 269	$ 1,831	$ 269	$ (1,319)
Comprehensive loss	$ (13,594)	$ (12,959)	$ (23,018)	$ (31,943)