Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 519,495	$ 401,857	$ 269,311
Cost of sales	350,497	274,255	167,627
Gross profit	168,998	127,602	101,684
Operating expenses:
Advertising and marketing	11,101	12,440	10,436
Selling, general and administrative	105,398	96,229	56,752
(Gain) loss on disputed mophie purchase price	(6,967)	24,317	0
Transaction costs	725	2,591	179
Impairment of intangible asset	1,959	0	0
Amortization of long-lived intangibles	12,047	13,385	8,453
Total operating expenses	124,263	148,962	75,820
Income (loss) from operations	44,735	(21,360)	25,864
Other income (expense):
Interest expense	(2,081)	(1,851)	(97)
Other income (expense)	698	(348)	(69)
Total other expense	(1,383)	(2,199)	(166)
Income (loss) before provision for income taxes	43,352	(23,559)	25,698
Income tax (provision) benefit	(28,252)	7,972	(10,111)
Net income (loss)	$ 15,100	$ (15,587)	$ 15,587
Earnings (loss) per share attributable to stockholders:
Basic earnings (loss) per share (in usd per share)	$ 0.54	$ (0.56)	$ 0.54
Diluted earnings (loss) per share (in usd per share)	$ 0.53	$ (0.56)	$ 0.54