Unaudited Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenue	$ 72,319	$ 87,030	$ 144,608	$ 169,404
Cost of revenue	48,398	57,778	95,759	113,625
Gross profit	23,921	29,252	48,849	55,779
Expenses:
Selling, general and administrative	21,982	23,021	47,435	46,588
Depreciation and amortization	2,391	2,797	5,189	5,473
Research and development	2,271	1,670	4,527	3,242
Impairment of inventory and long-lived assets	0	20,372	40,435	20,372
Total expenses	26,644	47,860	97,586	75,675
Loss from operations	(2,723)	(18,608)	(48,737)	(19,896)
Other expense:
Interest expense	(701)	(420)	(1,200)	(828)
Other expense, net	(48)	(2)	(158)	(227)
Total other expense	(749)	(422)	(1,358)	(1,055)
Loss before income taxes	(3,472)	(19,030)	(50,095)	(20,951)
Income tax benefit	1,192	6,483	17,630	6,889
Net loss	$ (2,280)	$ (12,547)	$ (32,465)	$ (14,062)
Loss per common share:
Basic loss per common share (in dollars per share)	$ (0.04)	$ (0.23)	$ (0.59)	$ (0.26)
Diluted loss per common share (in dollars per share)	$ (0.04)	$ (0.23)	$ (0.59)	$ (0.26)
Weighted average common shares:
Weighted average common shares used in computing basic loss per common share (in shares)	54,910	54,264	54,827	54,356
Weighted average common shares used in computing diluted loss per common share (in shares)	54,910	54,264	54,827	54,356