Segment Information (Segment Results) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenue	$ 16,554	$ 17,691	$ 50,461	$ 48,491
Cost of revenue	4,062	4,292	12,429	13,022
Gross profit	12,492	13,399	38,032	35,469
Operating expenses	15,342	18,508	48,504	58,201
Operating income (loss)	(2,850)	(5,109)	(10,472)	(22,732)
Costs incurred and charged to expense			965
Consumer Media
Segment Reporting Information [Line Items]
Revenue	2,543	3,632	9,197	8,738
Mobile Services
Segment Reporting Information [Line Items]
Revenue	6,400	6,895	19,551	20,831
Games
Segment Reporting Information [Line Items]
Revenue	7,611	7,164	21,713	18,922
Operating Segments \| Consumer Media
Segment Reporting Information [Line Items]
Revenue	2,543	3,632	9,197	8,738
Cost of revenue	593	705	1,723	2,341
Gross profit	1,950	2,927	7,474	6,397
Operating expenses	2,092	2,692	6,754	8,688
Operating income (loss)	(142)	235	720	(2,291)
Operating Segments \| Mobile Services
Segment Reporting Information [Line Items]
Revenue	6,400	6,895	19,551	20,831
Cost of revenue	1,511	1,721	4,989	5,634
Gross profit	4,889	5,174	14,562	15,197
Operating expenses	5,577	7,143	18,847	22,142
Operating income (loss)	(688)	(1,969)	(4,285)	(6,945)
Operating Segments \| Games
Segment Reporting Information [Line Items]
Revenue	7,611	7,164	21,713	18,922
Cost of revenue	1,955	1,934	5,707	5,259
Gross profit	5,656	5,230	16,006	13,663
Operating expenses	5,152	5,151	15,051	15,476
Operating income (loss)	504	79	955	(1,813)
Corporate
Segment Reporting Information [Line Items]
Cost of revenue	3	(68)	10	(212)
Operating expenses	2,521	3,522	7,852	11,895
Operating income (loss)	$ (2,524)	$ (3,454)	$ (7,862)	$ (11,683)

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