Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Revenue, net of refund liabilities	$ 43,320	$ 42,467	$ 122,143	$ 114,546
Operating expenses:
Cost of revenue	26,146	26,675	78,332	75,306
Selling, general and administrative expenses	12,521	12,189	36,594	34,149
Depreciation of property and equipment	1,713	1,133	5,296	3,462
Amortization of intangible assets	872	722	2,524	2,166
Acquisition-related adjustment (income) loss	(1,640)	0	(1,640)	0
Total operating expenses	39,612	40,719	121,106	115,083
Operating income (loss) from continuing operations	3,708	1,748	1,037	(537)
Foreign currency transaction losses (gains) on short-term intercompany balances	70	(418)	730	(1,927)
Interest expense, net	416	142	1,300	227
Other (income) loss	(1)	17	16	(177)
Income (loss) from continuing operations before income tax	3,223	2,007	(1,009)	1,340
Income tax expense	597	930	1,573	2,436
Net income (loss) from continuing operations	2,626	1,077	(2,582)	(1,096)
Discontinued operations:
Loss from discontinued operations	(325)	(344)	(684)	(1,029)
Income tax expense	0	0	0	0
Net loss from discontinued operations	(325)	(344)	(684)	(1,029)
Net income (loss)	$ 2,301	$ 733	$ (3,266)	$ (2,125)
Basic income (loss) per common share (Note 2):
Basic loss from continuing operations (in usd per share)	$ 0.11	$ 0.05	$ (0.12)	$ (0.05)
Basic loss from discontinued operations (in usd per share)	(0.01)	(0.02)	(0.02)	(0.05)
Total basic loss per common share (in usd per share)	0.10	0.03	(0.14)	(0.10)
Diluted income (loss) per common share (Note 2):
Diluted loss from continuing operations (in usd per share)	0.11	0.05	(0.11)	(0.05)
Diluted loss from discontinued operations (in usd per share)	(0.01)	(0.02)	(0.03)	(0.05)
Total diluted loss per common share (in usd per share)	$ 0.10	$ 0.03	$ (0.14)	$ (0.10)
Weighted-average common shares outstanding (Note 2):
Basic (shares)	23,558	22,498	23,142	22,225
Diluted (shares)	24,207	22,761	23,142	22,225