Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Amounts held in banks that are FDIC insured	$ 0	$ 340,000
Allowance for doubtful accounts receivable	1,806,000	1,028,000
Provision for sales returns	921,000	808,000
Shipping and handling expense	$ 12,500,000	$ 15,900,000