Summary of Significant Accounting Policies (Details 2) - Sales Returns [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Balance at beginning of period	$ 4,825	$ 2,054
Additions that reduced net sales	33,543	19,779
Deduction from reserves for current year returns	(32,911)	(17,008)
Balance at end of period	$ 5,457	$ 4,825