Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue	$ 46,309	$ 51,381	$ 48,363	$ 54,528	$ 61,030	$ 63,250	$ 56,150	$ 69,470	$ 200,581	$ 249,900	$ 223,146
Cost of revenue:
Platform commissions, royalties and other	17,467	18,918	18,534	20,320	22,251	25,890	21,231	26,310	75,239	95,682	80,735
Impairment of prepaid royalties and minimum guarantees	123	29,836	105	43	858	1,555	89		30,107	2,502	257
Impairment and amortization of intangible assets	2,812	7,320	2,336	2,324	2,325	2,360	2,434	2,434	14,792	9,553	4,767
Total cost of revenues	20,402	56,074	20,975	22,687	25,434	29,805	23,754	28,744	120,138	107,737	85,759
Gross profit	25,907	(4,693)	27,388	31,841	35,596	33,445	32,396	40,726	80,443	142,163	137,387
Operating expenses:
Research and development	20,766	20,080	20,721	20,312	20,001	16,304	18,308	18,243	81,879	72,856	64,284
Sales and marketing	14,387	10,104	10,935	12,624	10,729	12,302	12,771	12,438	48,050	48,240	45,076
General and administrative	8,134	7,011	7,096	7,984	6,838	4,419	7,429	7,406	30,225	26,092	25,019
Amortization of intangible assets					11	31	32	127	0	201	508
Restructuring charge		57	2,116	106	1,075				2,279	1,075	435
Total operating expenses	43,287	37,252	40,868	41,026	38,654	33,056	38,540	38,214	162,433	148,464	135,322
Income (loss) from operations	(17,380)	(41,945)	(13,480)	(9,185)	(3,058)	389	(6,144)	2,512	(81,990)	(6,301)	2,065
Interest and other income (expense), net	(114)	(1,653)	(4,453)	469	(134)	(152)	(174)	(284)	(5,751)	(743)	(1,472)
Loss before income taxes	(17,494)	(43,598)	(17,933)	(8,716)	(3,192)	237	(6,318)	2,228	(87,741)	(7,044)	593
Income tax benefit (provision)	280	(129)	(16)	166	234	(79)	809	(1,104)	301	(141)	7,555
Net (loss)/income	$ (17,214)	$ (43,727)	$ (17,949)	$ (8,550)	$ (2,958)	$ 158	$ (5,509)	$ 1,124	$ (87,440)	$ (7,185)	$ 8,148
Net (loss) income per share:
Basic	$ (0.13)	$ (0.33)	$ (0.14)	$ (0.07)	$ (0.02)	$ 0.00	$ (0.05)	$ 0.01	$ (0.66)	$ (0.06)	$ 0.09
Diluted	$ (0.13)	$ (0.33)	$ (0.14)	$ (0.07)	$ (0.02)	$ 0.00	$ (0.05)	$ 0.01	$ (0.66)	$ (0.06)	$ 0.08
Quarterly Financial Data [Abstract]
Restructuring charge		$ 57	$ 2,116	$ 106	$ 1,075				$ 2,279	$ 1,075	$ 435
Workforce
Operating expenses:
Restructuring charge									1,491	1,044	435
Quarterly Financial Data [Abstract]
Restructuring charge									$ 1,491	$ 1,044	$ 435
China and Korea [Member] | Workforce
Operating expenses:
Restructuring charge		11
Quarterly Financial Data [Abstract]
Restructuring charge		11
China and Washington [Member] | Workforce
Operating expenses:
Restructuring charge		48
Quarterly Financial Data [Abstract]
Restructuring charge		$ 48
Long Beach | Workforce
Operating expenses:
Restructuring charge				106
Quarterly Financial Data [Abstract]
Restructuring charge				$ 106
San Francisco, APAC, and Washington | Workforce
Operating expenses:
Restructuring charge			1,421
Quarterly Financial Data [Abstract]
Restructuring charge			1,421
China and Long Beach [Member] | Workforce
Operating expenses:
Restructuring charge			695
Quarterly Financial Data [Abstract]
Restructuring charge			$ 695